Tag Archives: eternalblue

OMG The Stupid It Burns

Post Syndicated from Robert Graham original https://blog.erratasec.com/2018/04/omg-stupid-it-burns.html

This article, pointed out by @TheGrugq, is stupid enough that it’s worth rebutting.

The article starts with the question “Why did the lessons of Stuxnet, Wannacry, Heartbleed and Shamoon go unheeded?“. It then proceeds to ignore the lessons of those things.
Some of the actual lessons should be things like how Stuxnet crossed air gaps, how Wannacry spread through flat Windows networking, how Heartbleed comes from technical debt, and how Shamoon furthers state aims by causing damage.
But this article doesn’t cover the technical lessons. Instead, it thinks the lesson should be the moral lesson, that we should take these things more seriously. But that’s stupid. It’s the sort of lesson people teach you that know nothing about the topic. When you have nothing of value to contribute to a topic you can always take the moral high road and criticize everyone for being morally weak for not taking it more seriously. Obviously, since doctors haven’t cured cancer yet, it’s because they don’t take the problem seriously.
The article continues to ignore the lesson of these cyber attacks and instead regales us with a list of military lessons from WW I and WW II. This makes the same flaw that many in the military make, trying to understand cyber through analogies with the real world. It’s not that such lessons could have no value, it’s that this article contains a poor list of them. It seems to consist of a random list of events that appeal to the author rather than events that have bearing on cybersecurity.
Then, in case we don’t get the point, the article bullies us with hyperbole, cliches, buzzwords, bombastic language, famous quotes, and citations. It’s hard to see how most of them actually apply to the text. Rather, it seems like they are included simply because he really really likes them.
The article invests much effort in discussing the buzzword “OODA loop”. Most attacks in cyberspace don’t have one. Instead, attackers flail around, trying lots of random things, overcoming defense with brute-force rather than an understanding of what’s going on. That’s obviously the case with Wannacry: it was an accident, with the perpetrator experimenting with what would happen if they added the ETERNALBLUE exploit to their existing ransomware code. The consequence was beyond anybody’s ability to predict.
You might claim that this is just the first stage, that they’ll loop around, observe Wannacry’s effects, orient themselves, decide, then act upon what they learned. Nope. Wannacry burned the exploit. It’s essentially removed any vulnerable systems from the public Internet, thereby making it impossible to use what they learned. It’s still active a year later, with infected systems behind firewalls busily scanning the Internet so that if you put a new system online that’s vulnerable, it’ll be taken offline within a few hours, before any other evildoer can take advantage of it.
See what I’m doing here? Learning the actual lessons of things like Wannacry? The thing the above article fails to do??
The article has a humorous paragraph on “defense in depth”, misunderstanding the term. To be fair, it’s the cybersecurity industry’s fault: they adopted then redefined the term. That’s why there’s two separate articles on Wikipedia: one for the old military term (as used in this article) and one for the new cybersecurity term.
As used in the cybersecurity industry, “defense in depth” means having multiple layers of security. Many organizations put all their defensive efforts on the perimeter, and none inside a network. The idea of “defense in depth” is to put more defenses inside the network. For example, instead of just one firewall at the edge of the network, put firewalls inside the network to segment different subnetworks from each other, so that a ransomware infection in the customer support computers doesn’t spread to sales and marketing computers.
The article talks about exploiting WiFi chips to bypass the defense in depth measures like browser sandboxes. This is conflating different types of attacks. A WiFi attack is usually considered a local attack, from somebody next to you in bar, rather than a remote attack from a server in Russia. Moreover, far from disproving “defense in depth” such WiFi attacks highlight the need for it. Namely, phones need to be designed so that successful exploitation of other microprocessors (namely, the WiFi, Bluetooth, and cellular baseband chips) can’t directly compromise the host system. In other words, once exploited with “Broadpwn”, a hacker would need to extend the exploit chain with another vulnerability in the hosts Broadcom WiFi driver rather than immediately exploiting a DMA attack across PCIe. This suggests that if PCIe is used to interface to peripherals in the phone that an IOMMU be used, for “defense in depth”.
Cybersecurity is a young field. There are lots of useful things that outsider non-techies can teach us. Lessons from military history would be well-received.
But that’s not this story. Instead, this story is by an outsider telling us we don’t know what we are doing, that they do, and then proceeds to prove they don’t know what they are doing. Their argument is based on a moral suasion and bullying us with what appears on the surface to be intellectual rigor, but which is in fact devoid of anything smart.
My fear, here, is that I’m going to be in a meeting where somebody has read this pretentious garbage, explaining to me why “defense in depth” is wrong and how we need to OODA faster. I’d rather nip this in the bud, pointing out if you found anything interesting from that article, you are wrong.

Why the crypto-backdoor side is morally corrupt

Post Syndicated from Robert Graham original https://blog.erratasec.com/2018/04/why-crypto-backdoor-side-is-morally.html

Crypto-backdoors for law enforcement is a reasonable position, but the side that argues for it adds things that are either outright lies or morally corrupt. Every year, the amount of digital evidence law enforcement has to solve crimes increases, yet they outrageously lie, claiming they are “going dark”, losing access to evidence. A weirder claim is that  those who oppose crypto-backdoors are nonetheless ethically required to make them work. This is morally corrupt.

That’s the point of this Lawfare post, which claims:

What I am saying is that those arguing that we should reject third-party access out of hand haven’t carried their research burden. … There are two reasons why I think there hasn’t been enough research to establish the no-third-party access position. First, research in this area is “taboo” among security researchers. … the second reason why I believe more research needs to be done: the fact that prominent non-government experts are publicly willing to try to build secure third-party-access solutions should make the information-security community question the consensus view. 

This is nonsense. It’s like claiming we haven’t cured the common cold because researchers haven’t spent enough effort at it. When researchers claim they’ve tried 10,000 ways to make something work, it’s like insisting they haven’t done enough because they haven’t tried 10,001 times.
Certainly, half the community doesn’t want to make such things work. Any solution for the “legitimate” law enforcement of the United States means a solution for illegitimate states like China and Russia which would use the feature to oppress their own people. Even if I believe it’s a net benefit to the United States, I would never attempt such research because of China and Russia.
But computer scientists notoriously ignore ethics in pursuit of developing technology. That describes the other half of the crypto community who would gladly work on the problem. The reason they haven’t come up with solutions is because the problem is hard, really hard.
The second reason the above argument is wrong: it says we should believe a solution is possible because some outsiders are willing to try. But as Yoda says, do or do not, there is no try. Our opinions on the difficulty of the problem don’t change simply because people are trying. Our opinions change when people are succeeding. People are always trying the impossible, that’s not evidence it’s possible.
The paper cherry picks things, like Intel CPU features, to make it seem like they are making forward progress. No. Intel’s SGX extensions are there for other reasons. Sure, it’s a new development, and new developments may change our opinion on the feasibility of law enforcement backdoors. But nowhere in talking about this new development have they actually proposes a solution to the backdoor problem. New developments happen all the time, and the pro-backdoor side is going to seize upon each and every one to claim that this, finally, solves the backdoor problem, without showing exactly how it solves the problem.

The Lawfare post does make one good argument, that there is no such thing as “absolute security”, and thus the argument is stupid that “crypto-backdoors would be less than absolute security”. Too often in the cybersecurity community we reject solutions that don’t provide “absolute security” while failing to acknowledge that “absolute security” is impossible.
But that’s not really what’s going on here. Cryptographers aren’t certain we’ve achieved even “adequate security” with current crypto regimes like SSL/TLS/HTTPS. Every few years we find horrible flaws in the old versions and have to develop new versions. If you steal somebody’s iPhone today, it’s so secure you can’t decrypt anything on it. But then if you hold it for 5 years, somebody will eventually figure out a hole and then you’ll be able to decrypt it — a hole that won’t affect Apple’s newer phones.
The reason we think we can’t get crypto-backdoors correct is simply because we can’t get crypto completely correct. It’s implausible that we can get the backdoors working securely when we still have so much trouble getting encryption working correctly in the first place.
Thus, we aren’t talking about “insignificantly less security”, we are talking about going from “barely adequate security” to “inadequate security”. Negotiating keys between you and a website is hard enough without simultaneously having to juggle keys with law enforcement organizations.

And finally, even if cryptographers do everything correctly law enforcement themselves haven’t proven themselves reliable. The NSA exposed its exploits (like the infamous ETERNALBLUE), and OPM lost all its security clearance records. If they can’t keep those secrets, it’s unreasonable to believe they can hold onto backdoor secrets. One of the problems cryptographers are expected to solve is partly this, to make it work in a such way that makes it unlikely law enforcement will lose its secrets.

Summary

This argument by the pro-backdoor side, that we in the crypto-community should do more to solve backdoors, it simply wrong. We’ve spent a lot of effort at this already. Many continue to work on this problem — the reason you haven’t heard much from them is because they haven’t had much success. It’s like blaming doctors for not doing more to work on interrogation drugs (truth serums). Sure, a lot of doctors won’t work on this because it’s distasteful, but at the same time, there are many drug companies who would love to profit by them. The reason they don’t exist is not because they aren’t spending enough money researching them, it’s because there is no plausible solution in sight.
Crypto-backdoors designed for law-enforcement will significantly harm your security. This may change in the future, but that’s the state of crypto today. You should trust the crypto experts on this, not lawyers.

WannaCry after one year

Post Syndicated from Robert Graham original https://blog.erratasec.com/2018/03/wannacry-after-one-year.html

In the news, Boeing (an aircraft maker) has been “targeted by a WannaCry virus attack”. Phrased this way, it’s implausible. There are no new attacks targeting people with WannaCry. There is either no WannaCry, or it’s simply a continuation of the attack from a year ago.


It’s possible what happened is that an anti-virus product called a new virus “WannaCry”. Virus families are often related, and sometimes a distant relative gets called the same thing. I know this watching the way various anti-virus products label my own software, which isn’t a virus, but which virus writers often include with their own stuff. The Lazarus group, which is believed to be responsible for WannaCry, have whole virus families like this. Thus, just because an AV product claims you are infected with WannaCry doesn’t mean it’s the same thing that everyone else is calling WannaCry.

Famously, WannaCry was the first virus/ransomware/worm that used the NSA ETERNALBLUE exploit. Other viruses have since added the exploit, and of course, hackers use it when attacking systems. It may be that a network intrusion detection system detected ETERNALBLUE, which people then assumed was due to WannaCry. It may actually have been an nPetya infection instead (nPetya was the second major virus/worm/ransomware to use the exploit).

Or it could be the real WannaCry, but it’s probably not a new “attack” that “targets” Boeing. Instead, it’s likely a continuation from WannaCry’s first appearance. WannaCry is a worm, which means it spreads automatically after it was launched, for years, without anybody in control. Infected machines still exist, unnoticed by their owners, attacking random machines on the Internet. If you plug in an unpatched computer onto the raw Internet, without the benefit of a firewall, it’ll get infected within an hour.

However, the Boeing manufacturing systems that were infected were not on the Internet, so what happened? The narrative from the news stories imply some nefarious hacker activity that “targeted” Boeing, but that’s unlikely.

We have now have over 15 years of experience with network worms getting into strange places disconnected and even “air gapped” from the Internet. The most common reason is laptops. Somebody takes their laptop to some place like an airport WiFi network, and gets infected. They put their laptop to sleep, then wake it again when they reach their destination, and plug it into the manufacturing network. At this point, the virus spreads and infects everything. This is especially the case with maintenance/support engineers, who often have specialized software they use to control manufacturing machines, for which they have a reason to connect to the local network even if it doesn’t have useful access to the Internet. A single engineer may act as a sort of Typhoid Mary, going from customer to customer, infecting each in turn whenever they open their laptop.

Another cause for infection is virtual machines. A common practice is to take “snapshots” of live machines and save them to backups. Should the virtual machine crash, instead of rebooting it, it’s simply restored from the backed up running image. If that backup image is infected, then bringing it out of sleep will allow the worm to start spreading.

Jake Williams claims he’s seen three other manufacturing networks infected with WannaCry. Why does manufacturing seem more susceptible? The reason appears to be the “killswitch” that stops WannaCry from running elsewhere. The killswitch uses a DNS lookup, stopping itself if it can resolve a certain domain. Manufacturing networks are largely disconnected from the Internet enough that such DNS lookups don’t work, so the domain can’t be found, so the killswitch doesn’t work. Thus, manufacturing systems are no more likely to get infected, but the lack of killswitch means the virus will continue to run, attacking more systems instead of immediately killing itself.

One solution to this would be to setup sinkhole DNS servers on the network that resolve all unknown DNS queries to a single server that logs all requests. This is trivially setup with most DNS servers. The logs will quickly identify problems on the network, as well as any hacker or virus activity. The side effect is that it would make this killswitch kill WannaCry. WannaCry isn’t sufficient reason to setup sinkhole servers, of course, but it’s something I’ve found generally useful in the past.

Conclusion

Something obviously happened to the Boeing plant, but the narrative is all wrong. Words like “targeted attack” imply things that likely didn’t happen. Facts are so loose in cybersecurity that it may not have even been WannaCry.

The real story is that the original WannaCry is still out there, still trying to spread. Simply put a computer on the raw Internet (without a firewall) and you’ll get attacked. That, somehow, isn’t news. Instead, what’s news is whenever that continued infection hits somewhere famous, like Boeing, even though (as Boeing claims) it had no important effect.

New White House Announcement on the Vulnerability Equities Process

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/11/new_white_house_1.html

The White House has released a new version of the Vulnerabilities Equities Process (VEP). This is the inter-agency process by which the US government decides whether to inform the software vendor of a vulnerability it finds, or keep it secret and use it to eavesdrop on or attack other systems. You can read the new policy or the fact sheet, but the best place to start is Cybersecurity Coordinator Rob Joyce’s blog post.

In considering a way forward, there are some key tenets on which we can build a better process.

Improved transparency is critical. The American people should have confidence in the integrity of the process that underpins decision making about discovered vulnerabilities. Since I took my post as Cybersecurity Coordinator, improving the VEP and ensuring its transparency have been key priorities, and we have spent the last few months reviewing our existing policy in order to improve the process and make key details about the VEP available to the public. Through these efforts, we have validated much of the existing process and ensured a rigorous standard that considers many potential equities.

The interests of all stakeholders must be fairly represented. At a high level we consider four major groups of equities: defensive equities; intelligence / law enforcement / operational equities; commercial equities; and international partnership equities. Additionally, ordinary people want to know the systems they use are resilient, safe, and sound. These core considerations, which have been incorporated into the VEP Charter, help to standardize the process by which decision makers weigh the benefit to national security and the national interest when deciding whether to disclose or restrict knowledge of a vulnerability.

Accountability of the process and those who operate it is important to establish confidence in those served by it. Our public release of the unclassified portions Charter will shed light on aspects of the VEP that were previously shielded from public review, including who participates in the VEP’s governing body, known as the Equities Review Board. We make it clear that departments and agencies with protective missions participate in VEP discussions, as well as other departments and agencies that have broader equities, like the Department of State and the Department of Commerce. We also clarify what categories of vulnerabilities are submitted to the process and ensure that any decision not to disclose a vulnerability will be reevaluated regularly. There are still important reasons to keep many of the specific vulnerabilities evaluated in the process classified, but we will release an annual report that provides metrics about the process to further inform the public about the VEP and its outcomes.

Our system of government depends on informed and vigorous dialogue to discover and make available the best ideas that our diverse society can generate. This publication of the VEP Charter will likely spark discussion and debate. This discourse is important. I also predict that articles will make breathless claims of “massive stockpiles” of exploits while describing the issue. That simply isn’t true. The annual reports and transparency of this effort will reinforce that fact.

Mozilla is pleased with the new charter. I am less so; it looks to me like the same old policy with some new transparency measures — which I’m not sure I trust. The devil is in the details, and we don’t know the details — and it has giant loopholes that pretty much anything can fall through:

The United States Government’s decision to disclose or restrict vulnerability information could be subject to restrictions by partner agreements and sensitive operations. Vulnerabilities that fall within these categories will be cataloged by the originating Department/Agency internally and reported directly to the Chair of the ERB. The details of these categories are outlined in Annex C, which is classified. Quantities of excepted vulnerabilities from each department and agency will be provided in ERB meetings to all members.

This is me from last June:

There’s a lot we don’t know about the VEP. The Washington Post says that the NSA used EternalBlue “for more than five years,” which implies that it was discovered after the 2010 process was put in place. It’s not clear if all vulnerabilities are given such consideration, or if bugs are periodically reviewed to determine if they should be disclosed. That said, any VEP that allows something as dangerous as EternalBlue — or the Cisco vulnerabilities that the Shadow Brokers leaked last August — to remain unpatched for years isn’t serving national security very well. As a former NSA employee said, the quality of intelligence that could be gathered was “unreal.” But so was the potential damage. The NSA must avoid hoarding vulnerabilities.

I stand by that, and am not sure the new policy changes anything.

More commentary.

Here’s more about the Windows vulnerabilities hoarded by the NSA and released by the Shadow Brokers.

EDITED TO ADD (11/18): More news.

EDITED TO ADD (11/22): Adam Shostack points out that the process does not cover design flaws or trade-offs, and that those need to be covered:

…we need the VEP to expand to cover those issues. I’m not going to claim that will be easy, that the current approach will translate, or that they should have waited to handle those before publishing. One obvious place it gets harder is the sources and methods tradeoff. But we need the internet to be a resilient and trustworthy infrastructure.

Zero-Day Vulnerabilities against Windows in the NSA Tools Released by the Shadow Brokers

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/07/zero-day_vulner.html

In April, the Shadow Brokers — presumably Russia — released a batch of Windows exploits from what is presumably the NSA. Included in that release were eight different Windows vulnerabilities. Given a presumed theft date of the data as sometime between 2012 and 2013 — based on timestamps of the documents and the limited Windows 8 support of the tools:

  • Three were already patched by Microsoft. That is, they were not zero days, and could only be used against unpatched targets. They are EMERALDTHREAD, EDUCATEDSCHOLAR, and ECLIPSEDWING.
  • One was discovered to have been used in the wild and patched in 2014: ESKIMOROLL.

  • Four were only patched when the NSA informed Microsoft about them in early 2017: ETERNALBLUE, ETERNALSYNERGY, ETERNALROMANCE, and ETERNALCHAMPION.

So of the five serious zero-day vulnerabilities against Windows in the NSA’s pocket, four were never independently discovered. This isn’t new news, but I haven’t seen this summary before.

Slowloris all the things

Post Syndicated from Robert Graham original http://blog.erratasec.com/2017/07/slowloris-all-things.html

At DEFCON, some researchers are going to announce a Slowloris-type exploit for SMB — SMBloris. I thought I’d write up some comments.

The original Slowloris from several years creates a ton of connections to a web server, but only sends partial headers. The server allocates a large amount of memory to handle the requests, expecting to free that memory soon when the requests are completed. But the requests are never completed, so the memory remains tied up indefinitely. Moreover, this also consumes a lot of CPU resources — every time Slowloris dribbles a few more bytes on the TCP connection is forces the CPU to walk through a lot of data structures to handle those bytes.

The thing about Slowloris is that it’s not specific to HTTP. It’s a principle that affects pretty much every service that listens on the Internet. For example, on Linux servers running NFS, you can exploit the RPC fragmentation feature in order to force the server to allocate all the memory in a box waiting for fragments that never arrive.

SMBloris does the same thing for SMB. It’s an easy attack to carry out in general, the only question is how much resources are required on the attacker’s side. That’s probably what this talk is about, causing the maximum consequences on the server with minimal resources on the attacker’s machine, thus allowing a Raspberry Pi to tie up all the resources on even the largest enterprise server.

According to the ThreatPost article, the attack was created looking at the NSA ETERNALBLUE exploit. That exploit works by causing the server to allocate memory chunks from fragmented requests. How to build a Slowloris exploit from this is then straightforward — just continue executing the first part of the ETERNALBLUE exploit, with larger chunks. I say “straightforward”, but of course, the researchers have probably discovered some additional clever tricks.

Samba, the SMB rewrite for non-Windows systems, probably falls victim to related problems. Maybe not this particular attack that affects Windows, but almost certainly something else. If not SMB, then the DCE-RPC service on top of it.

Microsoft has said they aren’t going to fix the SMBloris bug, and for good reason: it might be unfixable. Sure, there’s probably some kludge that fixes this specific script, but would still leave the system vulnerable to slight variations. The same reasoning applies to other services — Slowloris is an inherent problem in all Internet services and is not something easily addressed without re-writing the service from the ground up to specifically deal with the problem.

The best answer to Slowloris is the “langsec” discipline, which counsels us to separate “parsing” input from “processing” it. Most services combine the two, partially processing partial input. This should be changed to fully validate input consuming the least resources possible, before processing it. In other words, services should have a light-weight front-end that consumes the least resources possible, waiting for the request to complete, before it then forwards the request to the rest of the system.

NonPetya: no evidence it was a "smokescreen"

Post Syndicated from Robert Graham original http://blog.erratasec.com/2017/06/nonpetya-no-evidence-it-was-smokescreen.html

Many well-regarded experts claim that the not-Petya ransomware wasn’t “ransomware” at all, but a “wiper” whose goal was to destroy files, without any intent at letting victims recover their files. I want to point out that there is no real evidence of this.

Certainly, things look suspicious. For one thing, it certainly targeted the Ukraine. For another thing, it made several mistakes that prevent them from ever decrypting drives. Their email account was shutdown, and it corrupts the boot sector.

But these things aren’t evidence, they are problems. They are things needing explanation, not things that support our preferred conspiracy theory.

The simplest, Occam’s Razor explanation explanation is that they were simple mistakes. Such mistakes are common among ransomware. We think of virus writers as professional software developers who thoroughly test their code. Decades of evidence show the opposite, that such software is of poor quality with shockingly bad bugs.

It’s true that effectively, nPetya is a wiper. Matthieu Suiche‏ does a great job describing one flaw that prevents it working. @hasherezade does a great job explaining another flaw.  But best explanation isn’t that this is intentional. Even if these bugs didn’t exist, it’d still be a wiper if the perpetrators simply ignored the decryption requests. They need not intentionally make the decryption fail.

Thus, the simpler explanation is that it’s simply a bug. Ransomware authors test the bits they care about, and test less well the bits they don’t. It’s quite plausible to believe that just before shipping the code, they’d add a few extra features, and forget to regression test the entire suite. I mean, I do that all the time with my code.

Some have pointed to the sophistication of the code as proof that such simple errors are unlikely. This isn’t true. While it’s more sophisticated than WannaCry, it’s about average for the current state-of-the-art for ransomware in general. What people think of, such the Petya base, or using PsExec to spread throughout a Windows domain, is already at least a year old.

Indeed, the use of PsExec itself is a bit clumsy, when the code for doing the same thing is already public. It’s just a few calls to basic Windows networking APIs. A sophisticated virus would do this itself, rather than clumsily use PsExec.

Infamy doesn’t mean skill. People keep making the mistake that the more widespread something is in the news, the more skill, the more of a “conspiracy” there must be behind it. This is not true. Virus/worm writers often do newsworthy things by accident. Indeed, the history of worms, starting with the Morris Worm, has been things running out of control more than the author’s expectations.

What makes nPetya newsworthy isn’t the EternalBlue exploit or the wiper feature. Instead, the creators got lucky with MeDoc. The software is used by every major organization in the Ukraine, and at the same time, their website was horribly insecure — laughably insecure. Furthermore, it’s autoupdate feature didn’t check cryptographic signatures. No hacker can plan for this level of widespread incompetence — it’s just extreme luck.

Thus, the effect of bumbling around is something that hit the Ukraine pretty hard, but it’s not necessarily the intent of the creators. It’s like how the Slammer worm hit South Korea pretty hard, or how the Witty worm hit the DoD pretty hard. These things look “targeted”, especially to the victims, but it was by pure chance (provably so, in the case of Witty).

Certainly, MeDoc was targeted. But then, targeting a single organization is the norm for ransomware. They have to do it that way, giving each target a different Bitcoin address for payment. That it then spread to the entire Ukraine, and further, is the sort of thing that typically surprises worm writers.

Finally, there’s little reason to believe that there needs to be a “smokescreen”. Russian hackers are targeting the Ukraine all the time. Whether Russian hackers are to blame for “ransomware” vs. “wiper” makes little difference.

Conclusion

We know that Russian hackers are constantly targeting the Ukraine. Therefore, the theory that this was nPetya’s goal all along, to destroy Ukraines computers, is a good one.

Yet, there’s no actual “evidence” of this. nPetya’s issues are just as easily explained by normal software bugs. The smokescreen isn’t needed. The boot record bug isn’t needed. The single email address that was shutdown isn’t significant, since half of all ransomware uses the same technique.

The experts who disagree with me are really smart/experienced people who you should generally trust. It’s just that I can’t see their evidence.

Update: I wrote another blogpost about “survivorship bias“, refuting the claim by many experts talking about the sophistication of the spreading feature.


Update: comment asks “why is there no Internet spreading code?”. The answer is “I don’t know”, but unanswerable questions aren’t evidence of a conspiracy. “What aren’t there any stars in the background?” isn’t proof the moon landings are fake, such because you can’t answer the question. One guess is that you never want ransomware to spread that far, until you’ve figured out how to get payment from so many people.

NotPetya Ransomeware Wreaking Havoc

Post Syndicated from Darknet original http://feedproxy.google.com/~r/darknethackers/~3/0IfKiBP5jIo/

The latest splash has been made by the Petya or NotPetya Ransomware that exploded in Ukraine and is infecting companies all over the World. It’s getting some people in deep trouble as there’s no way to recover the files once encrypted. The malware seems to be trying to hide it’s intent as it doesn’t really […]

The post NotPetya Ransomeware…

Read the full post at darknet.org.uk

Some non-lessons from WannaCry

Post Syndicated from Robert Graham original http://blog.erratasec.com/2017/06/some-non-lessons-from-wannacry.html

This piece by Bruce Schneier needs debunking. I thought I’d list the things wrong with it.

The NSA 0day debate

Schneier’s description of the problem is deceptive:

When the US government discovers a vulnerability in a piece of software, however, it decides between two competing equities. It can keep it secret and use it offensively, to gather foreign intelligence, help execute search warrants, or deliver malware. Or it can alert the software vendor and see that the vulnerability is patched, protecting the country — and, for that matter, the world — from similar attacks by foreign governments and cybercriminals. It’s an either-or choice.

The government doesn’t “discover” vulnerabilities accidentally. Instead, when the NSA has a need for something specific, it acquires the 0day, either through internal research or (more often) buying from independent researchers.

The value of something is what you are willing to pay for it. If the NSA comes across a vulnerability accidentally, then the value to them is nearly zero. Obviously such vulns should be disclosed and fixed. Conversely, if the NSA is willing to pay $1 million to acquire a specific vuln for imminent use against a target, the offensive value is much greater than the fix value.

What Schneier is doing is deliberately confusing the two, combing the policy for accidentally found vulns with deliberately acquired vulns.

The above paragraph should read instead:

When the government discovers a vulnerability accidentally, it then decides to alert the software vendor to get it patched. When the government decides it needs as vuln for a specific offensive use, it acquires one that meets its needs, uses it, and keeps it secret. After spending so much money acquiring an offensive vuln, it would obviously be stupid to change this decision and not use it offensively.

Hoarding vulns

Schneier also says the NSA is “hoarding” vulns. The word has a couple inaccurate connotations.
One connotation is that the NSA is putting them on a heap inside a vault, not using them. The opposite is true: the NSA only acquires vulns it for which it has an active need. It uses pretty much all the vulns it acquires. That can be seen in the ShadowBroker dump, all the vulns listed are extremely useful to attackers, especially ETERNALBLUE. Efficiency is important to the NSA. Your efficiency is your basis for promotion. There are other people who make their careers finding waste in the NSA. If you are hoarding vulns and not using them, you’ll quickly get ejected from the NSA.
Another connotation is that the NSA is somehow keeping the vulns away from vendors. That’s like saying I’m hoarding naked selfies of myself. Yes, technically I’m keeping them away from you, but it’s not like they ever belong to you in the first place. The same is true the NSA. Had it never acquired the ETERNALBLUE 0day, it never would’ve been researched, never found.

The VEP

Schneier describes the “Vulnerability Equities Process” or “VEP”, a process that is supposed to manage the vulnerabilities the government gets.

There’s no evidence the VEP process has ever been used, at least not with 0days acquired by the NSA. The VEP allows exceptions for important vulns, and all the NSA vulns are important, so all are excepted from the process. Since the NSA is in charge of the VEP, of course, this is at the sole discretion of the NSA. Thus, the entire point of the VEP process goes away.

Moreover, it can’t work in many cases. The vulns acquired by the NSA often come with clauses that mean they can’t be shared.

New classes of vulns

One reason sellers forbid 0days from being shared is because they use new classes of vulnerabilities, such that sharing one 0day will effectively ruin a whole set of vulnerabilities. Schneier poo-poos this because he doesn’t see new classes of vulns in the ShadowBroker set.
This is wrong for two reasons. The first is that the ShadowBroker 0days are incomplete. There’s no iOS exploits, for example, and we know that iOS is a big target of the NSA.
Secondly, I’m not sure we’ve sufficiently analyzed the ShadowBroker exploits yet to realize there may be a new class of vuln. It’s easy to miss the fact that a single bug we see in the dump may actually be a whole new class of vulnerability. In the past, it’s often been the case that a new class was named only after finding many examples.
In any case, Schneier misses the point denying new classes of vulns exist. He should instead use the point to prove the value of disclosure, that instead of playing wack-a-mole fixing bugs one at a time, vendors would be able to fix whole classes of bugs at once.

Rediscovery

Schneier cites two studies that looked at how often vulnerabilities get rediscovered. In other words, he’s trying to measure the likelihood that some other government will find the bug and use it against us.
These studies are weak, scarcely better than anecdotal evidence. Schneier’s own study seems almost unrelated to the problem, and the Rand’s study cannot be replicated, as it relies upon private data. Also, there is little differentiation between important bugs (like SMB/MSRPC exploits and full-chain iOS exploits) and lesser bugs.
Whether from the Rand study or from anecdotes, we have good reason to believe that the longer an 0day exists, the less likely it’ll be rediscovered. Schneier argues that vulns should only be used for 6 months before being disclosed to a vendor. Anecdotes suggest otherwise, that if it hasn’t been rediscovered in the first year, it likely won’t ever be.
The Rand study was overwhelmingly clear on the issue that 0days are dramatically more likely to become obsolete than be rediscovered. The latest update to iOS will break an 0day, rather than somebody else rediscovering it. Win10 adoption will break older SMB exploits faster than rediscovery.
In any case, this post is about ETERNALBLUE specifically. What we learned from this specific bug is that it was used for at least 5 year without anybody else rediscovering it (before it was leaked). Chances are good it never would’ve been rediscovered, just made obsolete by Win10.

Notification is notification

All disclosure has the potential of leading to worms like WannaCry. The Conficker worm of 2008, for example, was written after Microsoft patched the underlying vulnerability.
Thus, had the NSA disclosed the bug in the normal way, chances are good it still would’ve been used for worming ransomware.
Yes, WannaCry had a head-start because ShadowBrokers published a working exploit, but this doesn’t appear to have made a difference. The Blaster worm (the first worm to compromise millions of computers) took roughly the same amount of time to create, and almost no details were made public about the vulnerability, other than the fact it was patched. (I know from personal experience — we used diff to find what changed in the patch in order to reverse engineer the 0day).
In other words, the damage the NSA is responsible for isn’t really the damage that came after it was patched — that was likely to happen anyway, as it does with normal vuln disclosure. Instead, the only damage the NSA can truly be held responsible for is the damage ahead of time, such as the months (years?) the ShadowBrokers possessed the exploits before they were patched.

Disclosed doesn’t mean fixed

One thing we’ve learned from 30 years of disclosure is that vendors ignore bugs.
We’ve gotten to the state where a few big companies like Microsoft and Apple will actually fix bugs, but the vast majority of vendors won’t. Even Microsoft and Apple have been known to sit on tricky bugs for over a year before fixing them.
And the only reason Microsoft and Apple have gotten to this state is because we, the community, bullied them into it. When we disclose bugs to them, we give them a deadline when we make the bug public, whether or not its been fixed.
The same goes for the NSA. If they quietly disclose bugs to vendors, in general, they won’t be fixed unless the NSA also makes the bug public within a certain time frame. Either Schneier has to argue that the NSA should do such public full-disclosures, or argue that disclosures won’t always lead to fixes.

Replacement SMB/MSRPC

The ETERNALBLUE vuln is so valuable to the NSA that it’s almost certainly seeking a replacement.
Again, I’m trying to debunk the impression Schneier tries to form that somehow the NSA stumbled upon ETERNALBLUE by accident to begin with. The opposite is true: remote exploits for the SMB (port 445) or MSRPC (port 135) services are some of the most valuable vulns, and the NSA will work hard to acquire them.

That it was leaked

The only issue here is that the 0day leaked. If the NSA can’t keep it’s weaponized toys secret, then maybe it shouldn’t have them.
Instead of processing this new piece of information, which is important, Schneier takes this opportunity to just re-hash the old inaccurate and deceptive VEP debate.

Conclusion

Except for a tiny number of people working for the NSA, none of us really know what’s going on with 0days inside government. Schneier’s comments seem more off-base than most. Like all activists, he deliberately uses language to deceive rather than explain (like “discover” instead of “acquire”). Like all activists, he seems obsessed with the VEP, even though as far as anybody can tell, it’s not used for NSA acquired vulns. He deliberate ignores things he should be an expert in, such as how all patches/disclosures sometimes lead to worms/exploits, and how not all disclosure leads to fixes.

WannaCry and Vulnerabilities

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2017/06/wannacry_and_vu.html

There is plenty of blame to go around for the WannaCry ransomware that spread throughout the Internet earlier this month, disrupting work at hospitals, factories, businesses, and universities. First, there are the writers of the malicious software, which blocks victims’ access to their computers until they pay a fee. Then there are the users who didn’t install the Windows security patch that would have prevented an attack. A small portion of the blame falls on Microsoft, which wrote the insecure code in the first place. One could certainly condemn the Shadow Brokers, a group of hackers with links to Russia who stole and published the National Security Agency attack tools that included the exploit code used in the ransomware. But before all of this, there was the NSA, which found the vulnerability years ago and decided to exploit it rather than disclose it.

All software contains bugs or errors in the code. Some of these bugs have security implications, granting an attacker unauthorized access to or control of a computer. These vulnerabilities are rampant in the software we all use. A piece of software as large and complex as Microsoft Windows will contain hundreds of them, maybe more. These vulnerabilities have obvious criminal uses that can be neutralized if patched. Modern software is patched all the time — either on a fixed schedule, such as once a month with Microsoft, or whenever required, as with the Chrome browser.

When the US government discovers a vulnerability in a piece of software, however, it decides between two competing equities. It can keep it secret and use it offensively, to gather foreign intelligence, help execute search warrants, or deliver malware. Or it can alert the software vendor and see that the vulnerability is patched, protecting the country — and, for that matter, the world — from similar attacks by foreign governments and cybercriminals. It’s an either-or choice. As former US Assistant Attorney General Jack Goldsmith has said, “Every offensive weapon is a (potential) chink in our defense — and vice versa.”

This is all well-trod ground, and in 2010 the US government put in place an interagency Vulnerabilities Equities Process (VEP) to help balance the trade-off. The details are largely secret, but a 2014 blog post by then President Barack Obama’s cybersecurity coordinator, Michael Daniel, laid out the criteria that the government uses to decide when to keep a software flaw undisclosed. The post’s contents were unsurprising, listing questions such as “How much is the vulnerable system used in the core Internet infrastructure, in other critical infrastructure systems, in the US economy, and/or in national security systems?” and “Does the vulnerability, if left unpatched, impose significant risk?” They were balanced by questions like “How badly do we need the intelligence we think we can get from exploiting the vulnerability?” Elsewhere, Daniel has noted that the US government discloses to vendors the “overwhelming majority” of the vulnerabilities that it discovers — 91 percent, according to NSA Director Michael S. Rogers.

The particular vulnerability in WannaCry is code-named EternalBlue, and it was discovered by the US government — most likely the NSA — sometime before 2014. The Washington Post reported both how useful the bug was for attack and how much the NSA worried about it being used by others. It was a reasonable concern: many of our national security and critical infrastructure systems contain the vulnerable software, which imposed significant risk if left unpatched. And yet it was left unpatched.

There’s a lot we don’t know about the VEP. The Washington Post says that the NSA used EternalBlue “for more than five years,” which implies that it was discovered after the 2010 process was put in place. It’s not clear if all vulnerabilities are given such consideration, or if bugs are periodically reviewed to determine if they should be disclosed. That said, any VEP that allows something as dangerous as EternalBlue — or the Cisco vulnerabilities that the Shadow Brokers leaked last August to remain unpatched for years isn’t serving national security very well. As a former NSA employee said, the quality of intelligence that could be gathered was “unreal.” But so was the potential damage. The NSA must avoid hoarding vulnerabilities.

Perhaps the NSA thought that no one else would discover EternalBlue. That’s another one of Daniel’s criteria: “How likely is it that someone else will discover the vulnerability?” This is often referred to as NOBUS, short for “nobody but us.” Can the NSA discover vulnerabilities that no one else will? Or are vulnerabilities discovered by one intelligence agency likely to be discovered by another, or by cybercriminals?

In the past few months, the tech community has acquired some data about this question. In one study, two colleagues from Harvard and I examined over 4,300 disclosed vulnerabilities in common software and concluded that 15 to 20 percent of them are rediscovered within a year. Separately, researchers at the Rand Corporation looked at a different and much smaller data set and concluded that fewer than six percent of vulnerabilities are rediscovered within a year. The questions the two papers ask are slightly different and the results are not directly comparable (we’ll both be discussing these results in more detail at the Black Hat Conference in July), but clearly, more research is needed.

People inside the NSA are quick to discount these studies, saying that the data don’t reflect their reality. They claim that there are entire classes of vulnerabilities the NSA uses that are not known in the research world, making rediscovery less likely. This may be true, but the evidence we have from the Shadow Brokers is that the vulnerabilities that the NSA keeps secret aren’t consistently different from those that researchers discover. And given the alarming ease with which both the NSA and CIA are having their attack tools stolen, rediscovery isn’t limited to independent security research.

But even if it is difficult to make definitive statements about vulnerability rediscovery, it is clear that vulnerabilities are plentiful. Any vulnerabilities that are discovered and used for offense should only remain secret for as short a time as possible. I have proposed six months, with the right to appeal for another six months in exceptional circumstances. The United States should satisfy its offensive requirements through a steady stream of newly discovered vulnerabilities that, when fixed, also improve the country’s defense.

The VEP needs to be reformed and strengthened as well. A report from last year by Ari Schwartz and Rob Knake, who both previously worked on cybersecurity policy at the White House National Security Council, makes some good suggestions on how to further formalize the process, increase its transparency and oversight, and ensure periodic review of the vulnerabilities that are kept secret and used for offense. This is the least we can do. A bill recently introduced in both the Senate and the House calls for this and more.

In the case of EternalBlue, the VEP did have some positive effects. When the NSA realized that the Shadow Brokers had stolen the tool, it alerted Microsoft, which released a patch in March. This prevented a true disaster when the Shadow Brokers exposed the vulnerability on the Internet. It was only unpatched systems that were susceptible to WannaCry a month later, including versions of Windows so old that Microsoft normally didn’t support them. Although the NSA must take its share of the responsibility, no matter how good the VEP is, or how many vulnerabilities the NSA reports and the vendors fix, security won’t improve unless users download and install patches, and organizations take responsibility for keeping their software and systems up to date. That is one of the important lessons to be learned from WannaCry.

This essay originally appeared in Foreign Affairs.

Windows XP Too Unstable To Spread WannaCry

Post Syndicated from Darknet original http://feedproxy.google.com/~r/darknethackers/~3/j_usdwvHhp4/

Not a super serious article this one, but I found it very entertaining – apparently, Windows XP has a BSOD (Blue Screen of Death) when faced with a WannaCry infection. There’s a very extension analysis of WannaCry here where this information comes from WannaCry: Two Weeks and 16 Million Averted Ransoms Later. Yes, WannaCrypt can […]

The…

Read the full post at darknet.org.uk