Tag Archives: cliché

Let’s stop talking about password strength

Post Syndicated from Robert Graham original https://blog.erratasec.com/2018/04/lets-stop-talking-about-password.html

Picture from EFF — CC-BY license

Near the top of most security recommendations is to use “strong passwords”. We need to stop doing this.

Yes, weak passwords can be a problem. If a website gets hacked, weak passwords are easier to crack. It’s not that this is wrong advice.

On the other hand, it’s not particularly good advice, either. It’s far down the list of important advice that people need to remember. “Weak passwords” are nowhere near the risk of “password reuse”. When your Facebook or email account gets hacked, it’s because you used the same password across many websites, not because you used a weak password.

Important websites, where the strength of your password matters, already take care of the problem. They use strong, salted hashes on the backend to protect the password. On the frontend, they force passwords to be a certain length and a certain complexity. Maybe the better advice is to not trust any website that doesn’t enforce stronger passwords (minimum of 8 characters consisting of both letters and non-letters).

To some extent, this “strong password” advice has become obsolete. A decade ago, websites had poor protection (MD5 hashes) and no enforcement of complexity, so it was up to the user to choose strong passwords. Now that important websites have changed their behavior, such as using bcrypt, there is less onus on the user.

But the real issue here is that “strong password” advice reflects the evil, authoritarian impulses of the infosec community. Instead of measuring insecurity in terms of costs vs. benefits, risks vs. rewards, we insist that it’s an issue of moral weakness. We pretend that flaws happen because people are greedy, lazy, and ignorant. We pretend that security is its own goal, a benefit we should achieve, rather than a cost we must endure.

We like giving moral advice because it’s easy: just be “stronger”. Discussing “password reuse” is more complicated, forcing us discuss password managers, writing down passwords on paper, that it’s okay to reuse passwords for crappy websites you don’t care about, and so on.

What I’m trying to say is that the moral weakness here is us. Rather then give pertinent advice we give lazy advice. We give the advice that victim shames them for being weak while pretending that we are strong.

So stop telling people to use strong passwords. It’s crass advice on your part and largely unhelpful for your audience, distracting them from the more important things.

"Responsible encryption" fallacies

Post Syndicated from Robert Graham original http://blog.erratasec.com/2017/10/responsible-encryption-fallacies.html

Deputy Attorney General Rod Rosenstein gave a speech recently calling for “Responsible Encryption” (aka. “Crypto Backdoors”). It’s full of dangerous ideas that need to be debunked.

The importance of law enforcement

The first third of the speech talks about the importance of law enforcement, as if it’s the only thing standing between us and chaos. It cites the 2016 Mirai attacks as an example of the chaos that will only get worse without stricter law enforcement.

But the Mira case demonstrated the opposite, how law enforcement is not needed. They made no arrests in the case. A year later, they still haven’t a clue who did it.

Conversely, we technologists have fixed the major infrastructure issues. Specifically, those affected by the DNS outage have moved to multiple DNS providers, including a high-capacity DNS provider like Google and Amazon who can handle such large attacks easily.

In other words, we the people fixed the major Mirai problem, and law-enforcement didn’t.

Moreover, instead being a solution to cyber threats, law enforcement has become a threat itself. The DNC didn’t have the FBI investigate the attacks from Russia likely because they didn’t want the FBI reading all their files, finding wrongdoing by the DNC. It’s not that they did anything actually wrong, but it’s more like that famous quote from Richelieu “Give me six words written by the most honest of men and I’ll find something to hang him by”. Give all your internal emails over to the FBI and I’m certain they’ll find something to hang you by, if they want.
Or consider the case of Andrew Auernheimer. He found AT&T’s website made public user accounts of the first iPad, so he copied some down and posted them to a news site. AT&T had denied the problem, so making the problem public was the only way to force them to fix it. Such access to the website was legal, because AT&T had made the data public. However, prosecutors disagreed. In order to protect the powerful, they twisted and perverted the law to put Auernheimer in jail.

It’s not that law enforcement is bad, it’s that it’s not the unalloyed good Rosenstein imagines. When law enforcement becomes the thing Rosenstein describes, it means we live in a police state.

Where law enforcement can’t go

Rosenstein repeats the frequent claim in the encryption debate:

Our society has never had a system where evidence of criminal wrongdoing was totally impervious to detection

Of course our society has places “impervious to detection”, protected by both legal and natural barriers.

An example of a legal barrier is how spouses can’t be forced to testify against each other. This barrier is impervious.

A better example, though, is how so much of government, intelligence, the military, and law enforcement itself is impervious. If prosecutors could gather evidence everywhere, then why isn’t Rosenstein prosecuting those guilty of CIA torture?

Oh, you say, government is a special exception. If that were the case, then why did Rosenstein dedicate a precious third of his speech discussing the “rule of law” and how it applies to everyone, “protecting people from abuse by the government”. It obviously doesn’t, there’s one rule of government and a different rule for the people, and the rule for government means there’s lots of places law enforcement can’t go to gather evidence.

Likewise, the crypto backdoor Rosenstein is demanding for citizens doesn’t apply to the President, Congress, the NSA, the Army, or Rosenstein himself.

Then there are the natural barriers. The police can’t read your mind. They can only get the evidence that is there, like partial fingerprints, which are far less reliable than full fingerprints. They can’t go backwards in time.

I mention this because encryption is a natural barrier. It’s their job to overcome this barrier if they can, to crack crypto and so forth. It’s not our job to do it for them.

It’s like the camera that increasingly comes with TVs for video conferencing, or the microphone on Alexa-style devices that are always recording. This suddenly creates evidence that the police want our help in gathering, such as having the camera turned on all the time, recording to disk, in case the police later gets a warrant, to peer backward in time what happened in our living rooms. The “nothing is impervious” argument applies here as well. And it’s equally bogus here. By not helping police by not recording our activities, we aren’t somehow breaking some long standing tradit

And this is the scary part. It’s not that we are breaking some ancient tradition that there’s no place the police can’t go (with a warrant). Instead, crypto backdoors breaking the tradition that never before have I been forced to help them eavesdrop on me, even before I’m a suspect, even before any crime has been committed. Sure, laws like CALEA force the phone companies to help the police against wrongdoers — but here Rosenstein is insisting I help the police against myself.

Balance between privacy and public safety

Rosenstein repeats the frequent claim that encryption upsets the balance between privacy/safety:

Warrant-proof encryption defeats the constitutional balance by elevating privacy above public safety.

This is laughable, because technology has swung the balance alarmingly in favor of law enforcement. Far from “Going Dark” as his side claims, the problem we are confronted with is “Going Light”, where the police state monitors our every action.

You are surrounded by recording devices. If you walk down the street in town, outdoor surveillance cameras feed police facial recognition systems. If you drive, automated license plate readers can track your route. If you make a phone call or use a credit card, the police get a record of the transaction. If you stay in a hotel, they demand your ID, for law enforcement purposes.

And that’s their stuff, which is nothing compared to your stuff. You are never far from a recording device you own, such as your mobile phone, TV, Alexa/Siri/OkGoogle device, laptop. Modern cars from the last few years increasingly have always-on cell connections and data recorders that record your every action (and location).

Even if you hike out into the country, when you get back, the FBI can subpoena your GPS device to track down your hidden weapon’s cache, or grab the photos from your camera.

And this is all offline. So much of what we do is now online. Of the photographs you own, fewer than 1% are printed out, the rest are on your computer or backed up to the cloud.

Your phone is also a GPS recorder of your exact position all the time, which if the government wins the Carpenter case, they police can grab without a warrant. Tagging all citizens with a recording device of their position is not “balance” but the premise for a novel more dystopic than 1984.

If suspected of a crime, which would you rather the police searched? Your person, houses, papers, and physical effects? Or your mobile phone, computer, email, and online/cloud accounts?

The balance of privacy and safety has swung so far in favor of law enforcement that rather than debating whether they should have crypto backdoors, we should be debating how to add more privacy protections.

“But it’s not conclusive”

Rosenstein defends the “going light” (“Golden Age of Surveillance”) by pointing out it’s not always enough for conviction. Nothing gives a conviction better than a person’s own words admitting to the crime that were captured by surveillance. This other data, while copious, often fails to convince a jury beyond a reasonable doubt.
This is nonsense. Police got along well enough before the digital age, before such widespread messaging. They solved terrorist and child abduction cases just fine in the 1980s. Sure, somebody’s GPS location isn’t by itself enough — until you go there and find all the buried bodies, which leads to a conviction. “Going dark” imagines that somehow, the evidence they’ve been gathering for centuries is going away. It isn’t. It’s still here, and matches up with even more digital evidence.
Conversely, a person’s own words are not as conclusive as you think. There’s always missing context. We quickly get back to the Richelieu “six words” problem, where captured communications are twisted to convict people, with defense lawyers trying to untwist them.

Rosenstein’s claim may be true, that a lot of criminals will go free because the other electronic data isn’t convincing enough. But I’d need to see that claim backed up with hard studies, not thrown out for emotional impact.

Terrorists and child molesters

You can always tell the lack of seriousness of law enforcement when they bring up terrorists and child molesters.
To be fair, sometimes we do need to talk about terrorists. There are things unique to terrorism where me may need to give government explicit powers to address those unique concerns. For example, the NSA buys mobile phone 0day exploits in order to hack terrorist leaders in tribal areas. This is a good thing.
But when terrorists use encryption the same way everyone else does, then it’s not a unique reason to sacrifice our freedoms to give the police extra powers. Either it’s a good idea for all crimes or no crimes — there’s nothing particular about terrorism that makes it an exceptional crime. Dead people are dead. Any rational view of the problem relegates terrorism to be a minor problem. More citizens have died since September 8, 2001 from their own furniture than from terrorism. According to studies, the hot water from the tap is more of a threat to you than terrorists.
Yes, government should do what they can to protect us from terrorists, but no, it’s not so bad of a threat that requires the imposition of a military/police state. When people use terrorism to justify their actions, it’s because they trying to form a military/police state.
A similar argument works with child porn. Here’s the thing: the pervs aren’t exchanging child porn using the services Rosenstein wants to backdoor, like Apple’s Facetime or Facebook’s WhatsApp. Instead, they are exchanging child porn using custom services they build themselves.
Again, I’m (mostly) on the side of the FBI. I support their idea of buying 0day exploits in order to hack the web browsers of visitors to the secret “PlayPen” site. This is something that’s narrow to this problem and doesn’t endanger the innocent. On the other hand, their calls for crypto backdoors endangers the innocent while doing effectively nothing to address child porn.
Terrorists and child molesters are a clichéd, non-serious excuse to appeal to our emotions to give up our rights. We should not give in to such emotions.

Definition of “backdoor”

Rosenstein claims that we shouldn’t call backdoors “backdoors”:

No one calls any of those functions [like key recovery] a “back door.”  In fact, those capabilities are marketed and sought out by many users.

He’s partly right in that we rarely refer to PGP’s key escrow feature as a “backdoor”.

But that’s because the term “backdoor” refers less to how it’s done and more to who is doing it. If I set up a recovery password with Apple, I’m the one doing it to myself, so we don’t call it a backdoor. If it’s the police, spies, hackers, or criminals, then we call it a “backdoor” — even it’s identical technology.

Wikipedia uses the key escrow feature of the 1990s Clipper Chip as a prime example of what everyone means by “backdoor“. By “no one”, Rosenstein is including Wikipedia, which is obviously incorrect.

Though in truth, it’s not going to be the same technology. The needs of law enforcement are different than my personal key escrow/backup needs. In particular, there are unsolvable problems, such as a backdoor that works for the “legitimate” law enforcement in the United States but not for the “illegitimate” police states like Russia and China.

I feel for Rosenstein, because the term “backdoor” does have a pejorative connotation, which can be considered unfair. But that’s like saying the word “murder” is a pejorative term for killing people, or “torture” is a pejorative term for torture. The bad connotation exists because we don’t like government surveillance. I mean, honestly calling this feature “government surveillance feature” is likewise pejorative, and likewise exactly what it is that we are talking about.


Rosenstein focuses his arguments on “providers”, like Snapchat or Apple. But this isn’t the question.

The question is whether a “provider” like Telegram, a Russian company beyond US law, provides this feature. Or, by extension, whether individuals should be free to install whatever software they want, regardless of provider.

Telegram is a Russian company that provides end-to-end encryption. Anybody can download their software in order to communicate so that American law enforcement can’t eavesdrop. They aren’t going to put in a backdoor for the U.S. If we succeed in putting backdoors in Apple and WhatsApp, all this means is that criminals are going to install Telegram.

If the, for some reason, the US is able to convince all such providers (including Telegram) to install a backdoor, then it still doesn’t solve the problem, as uses can just build their own end-to-end encryption app that has no provider. It’s like email: some use the major providers like GMail, others setup their own email server.

Ultimately, this means that any law mandating “crypto backdoors” is going to target users not providers. Rosenstein tries to make a comparison with what plain-old telephone companies have to do under old laws like CALEA, but that’s not what’s happening here. Instead, for such rules to have any effect, they have to punish users for what they install, not providers.

This continues the argument I made above. Government backdoors is not something that forces Internet services to eavesdrop on us — it forces us to help the government spy on ourselves.
Rosenstein tries to address this by pointing out that it’s still a win if major providers like Apple and Facetime are forced to add backdoors, because they are the most popular, and some terrorists/criminals won’t move to alternate platforms. This is false. People with good intentions, who are unfairly targeted by a police state, the ones where police abuse is rampant, are the ones who use the backdoored products. Those with bad intentions, who know they are guilty, will move to the safe products. Indeed, Telegram is already popular among terrorists because they believe American services are already all backdoored. 
Rosenstein is essentially demanding the innocent get backdoored while the guilty don’t. This seems backwards. This is backwards.

Apple is morally weak

The reason I’m writing this post is because Rosenstein makes a few claims that cannot be ignored. One of them is how he describes Apple’s response to government insistence on weakening encryption doing the opposite, strengthening encryption. He reasons this happens because:

Of course they [Apple] do. They are in the business of selling products and making money. 

We [the DoJ] use a different measure of success. We are in the business of preventing crime and saving lives. 

He swells in importance. His condescending tone ennobles himself while debasing others. But this isn’t how things work. He’s not some white knight above the peasantry, protecting us. He’s a beat cop, a civil servant, who serves us.

A better phrasing would have been:

They are in the business of giving customers what they want.

We are in the business of giving voters what they want.

Both sides are doing the same, giving people what they want. Yes, voters want safety, but they also want privacy. Rosenstein imagines that he’s free to ignore our demands for privacy as long has he’s fulfilling his duty to protect us. He has explicitly rejected what people want, “we use a different measure of success”. He imagines it’s his job to tell us where the balance between privacy and safety lies. That’s not his job, that’s our job. We, the people (and our representatives), make that decision, and it’s his job is to do what he’s told. His measure of success is how well he fulfills our wishes, not how well he satisfies his imagined criteria.

That’s why those of us on this side of the debate doubt the good intentions of those like Rosenstein. He criticizes Apple for wanting to protect our rights/freedoms, and declare they measure success differently.

They are willing to be vile

Rosenstein makes this argument:

Companies are willing to make accommodations when required by the government. Recent media reports suggest that a major American technology company developed a tool to suppress online posts in certain geographic areas in order to embrace a foreign government’s censorship policies. 

Let me translate this for you:

Companies are willing to acquiesce to vile requests made by police-states. Therefore, they should acquiesce to our vile police-state requests.

It’s Rosenstein who is admitting here is that his requests are those of a police-state.

Constitutional Rights

Rosenstein says:

There is no constitutional right to sell warrant-proof encryption.

Maybe. It’s something the courts will have to decide. There are many 1st, 2nd, 3rd, 4th, and 5th Amendment issues here.
The reason we have the Bill of Rights is because of the abuses of the British Government. For example, they quartered troops in our homes, as a way of punishing us, and as a way of forcing us to help in our own oppression. The troops weren’t there to defend us against the French, but to defend us against ourselves, to shoot us if we got out of line.

And that’s what crypto backdoors do. We are forced to be agents of our own oppression. The principles enumerated by Rosenstein apply to a wide range of even additional surveillance. With little change to his speech, it can equally argue why the constant TV video surveillance from 1984 should be made law.

Let’s go back and look at Apple. It is not some base company exploiting consumers for profit. Apple doesn’t have guns, they cannot make people buy their product. If Apple doesn’t provide customers what they want, then customers vote with their feet, and go buy an Android phone. Apple isn’t providing encryption/security in order to make a profit — it’s giving customers what they want in order to stay in business.
Conversely, if we citizens don’t like what the government does, tough luck, they’ve got the guns to enforce their edicts. We can’t easily vote with our feet and walk to another country. A “democracy” is far less democratic than capitalism. Apple is a minority, selling phones to 45% of the population, and that’s fine, the minority get the phones they want. In a Democracy, where citizens vote on the issue, those 45% are screwed, as the 55% impose their will unwanted onto the remainder.

That’s why we have the Bill of Rights, to protect the 49% against abuse by the 51%. Regardless whether the Supreme Court agrees the current Constitution, it is the sort right that might exist regardless of what the Constitution says. 

Obliged to speak the truth

Here is the another part of his speech that I feel cannot be ignored. We have to discuss this:

Those of us who swear to protect the rule of law have a different motivation.  We are obliged to speak the truth.

The truth is that “going dark” threatens to disable law enforcement and enable criminals and terrorists to operate with impunity.

This is not true. Sure, he’s obliged to say the absolute truth, in court. He’s also obliged to be truthful in general about facts in his personal life, such as not lying on his tax return (the sort of thing that can get lawyers disbarred).

But he’s not obliged to tell his spouse his honest opinion whether that new outfit makes them look fat. Likewise, Rosenstein knows his opinion on public policy doesn’t fall into this category. He can say with impunity that either global warming doesn’t exist, or that it’ll cause a biblical deluge within 5 years. Both are factually untrue, but it’s not going to get him fired.

And this particular claim is also exaggerated bunk. While everyone agrees encryption makes law enforcement’s job harder than with backdoors, nobody honestly believes it can “disable” law enforcement. While everyone agrees that encryption helps terrorists, nobody believes it can enable them to act with “impunity”.

I feel bad here. It’s a terrible thing to question your opponent’s character this way. But Rosenstein made this unavoidable when he clearly, with no ambiguity, put his integrity as Deputy Attorney General on the line behind the statement that “going dark threatens to disable law enforcement and enable criminals and terrorists to operate with impunity”. I feel it’s a bald face lie, but you don’t need to take my word for it. Read his own words yourself and judge his integrity.


Rosenstein’s speech includes repeated references to ideas like “oath”, “honor”, and “duty”. It reminds me of Col. Jessup’s speech in the movie “A Few Good Men”.

If you’ll recall, it was rousing speech, “you want me on that wall” and “you use words like honor as a punchline”. Of course, since he was violating his oath and sending two privates to death row in order to avoid being held accountable, it was Jessup himself who was crapping on the concepts of “honor”, “oath”, and “duty”.

And so is Rosenstein. He imagines himself on that wall, doing albeit terrible things, justified by his duty to protect citizens. He imagines that it’s he who is honorable, while the rest of us not, even has he utters bald faced lies to further his own power and authority.

We activists oppose crypto backdoors not because we lack honor, or because we are criminals, or because we support terrorists and child molesters. It’s because we value privacy and government officials who get corrupted by power. It’s not that we fear Trump becoming a dictator, it’s that we fear bureaucrats at Rosenstein’s level becoming drunk on authority — which Rosenstein demonstrably has. His speech is a long train of corrupt ideas pursuing the same object of despotism — a despotism we oppose.

In other words, we oppose crypto backdoors because it’s not a tool of law enforcement, but a tool of despotism.

ROI is not a cybersecurity concept

Post Syndicated from Robert Graham original http://blog.erratasec.com/2017/08/roi-is-not-cybersecurity-concept.html

In the cybersecurity community, much time is spent trying to speak the language of business, in order to communicate to business leaders our problems. One way we do this is trying to adapt the concept of “return on investment” or “ROI” to explain why they need to spend more money. Stop doing this. It’s nonsense. ROI is a concept pushed by vendors in order to justify why you should pay money for their snake oil security products. Don’t play the vendor’s game.

The correct concept is simply “risk analysis”. Here’s how it works.

List out all the risks. For each risk, calculate:

  • How often it occurs.
  • How much damage it does.
  • How to mitigate it.
  • How effective the mitigation is (reduces chance and/or cost).
  • How much the mitigation costs.

If you have risk of something that’ll happen once-per-day on average, costing $1000 each time, then a mitigation costing $500/day that reduces likelihood to once-per-week is a clear win for investment.

Now, ROI should in theory fit directly into this model. If you are paying $500/day to reduce that risk, I could use ROI to show you hypothetical products that will …

  • …reduce the remaining risk to once-per-month for an additional $10/day.
  • …replace that $500/day mitigation with a $400/day mitigation.

But this is never done. Companies don’t have a sophisticated enough risk matrix in order to plug in some ROI numbers to reduce cost/risk. Instead, ROI is a calculation is done standalone by a vendor pimping product, or a security engineer building empires within the company.

If you haven’t done risk analysis to begin with (and almost none of you have), then ROI calculations are pointless.

But there are further problems. This is risk analysis as done in industries like oil and gas, which have inanimate risk. Almost all their risks are due to accidental failures, like in the Deep Water Horizon incident. In our industry, cybersecurity, risks are animate — by hackers. Our risk models are based on trying to guess what hackers might do.

An example of this problem is when our drug company jacks up the price of an HIV drug, Anonymous hackers will break in and dump all our financial data, and our CFO will go to jail. A lot of our risks come now from the technical side, but the whims and fads of the hacker community.

Another example is when some Google researcher finds a vuln in WordPress, and our website gets hacked by that three months from now. We have to forecast not only what hackers can do now, but what they might be able to do in the future.

Finally, there is this problem with cybersecurity that we really can’t distinguish between pesky and existential threats. Take ransomware. A lot of large organizations have just gotten accustomed to just wiping a few worker’s machines every day and restoring from backups. It’s a small, pesky problem of little consequence. Then one day a ransomware gets domain admin privileges and takes down the entire business for several weeks, as happened after #nPetya. Inevitably our risk models always come down on the high side of estimates, with us claiming that all threats are existential, when in fact, most companies continue to survive major breaches.

These difficulties with risk analysis leads us to punting on the problem altogether, but that’s not the right answer. No matter how faulty our risk analysis is, we still have to go through the exercise.

One model of how to do this calculation is architecture. We know we need a certain number of toilets per building, even without doing ROI on the value of such toilets. The same is true for a lot of security engineering. We know we need firewalls, encryption, and OWASP hardening, even without specifically doing a calculation. Passwords and session cookies need to go across SSL. That’s the starting point from which we start to analysis risks and mitigations — what we need beyond SSL, for example.

So stop using “ROI”, or worse, the abomination “ROSI”. Start doing risk analysis.

Fail your way to perfection

Post Syndicated from Olympia Brown original https://www.raspberrypi.org/blog/fail-perfection/

As educators and makers at Raspberry Pi, we think a lot about failure and how to deal with it constructively. Much has been written about the importance of failure to design and engineering projects. It is undoubtedly true that you can learn a lot from your mistakes, like getting the wrong size of part, mistyping your code, or not measuring when doing your DIY. The importance of failure has even become a bit of a common trope: just think of those slightly annoying inspirational quotes attributed to famous historical figures which you find all over social media.


I have not failed. I’ve just found 10,000 ways that won’t work. Thomas Edison.

Failure can be good!

But, as with many a cliché, there is an underlying truth that it is worth revisiting. Designing, engineering, and creating all involve making mistakes along the way. Even though failures feel bad, by reaching out when something goes wrong, you can call on the expertise of your community, learn, and make the final result better.

However, we often think failing also makes us look bad, so we don’t talk about it as an essential part of the process that got us to the end stage. We make things shiny and glossy to big-up our success, putting all the focus on the result. This tendency is, however, not necessarily helpful if we want to help educate others. As Jonathan Sanderson of NUSTEM puts it:

Jonathan Sanderson on Twitter

stem educators: worth noting: confessions of rank stupidity in digital making get responses, sympathy, offers of help on Twitter. (1/2)

Jonathan Sanderson on Twitter

yet our write-ups only feature the things we did right. Mis-steps and recovery from failure are key parts of process. (2/2)

The NUSTEM team truly believes in this: when sharing their builds, they include a section on what they would do differently next time. By highlighting the journey, and the mistakes made along the way, they are not only helping those that also want to go on that journey, they are also demystifying the process a bit.

Celebrate your fails

Because failure feels bad, we don’t routinely celebrate it. But there are niches where failure is celebrated: Simone Giertz’s (slightly sweary) YouTube videos are a great example. And then there is Hebocon, the Japanese competition for cruddy robots. In fact, the organisers of Hebocon make a great point: crafts that do not go as intended are interesting.

This is as much true when working with young people as it is in the wider world. In Pioneers, we also want to do our bit to celebrate failure. Our judges don’t just watch the teams’ videos to see how they overcame what went wrong along the way, they also have an award category that celebrates wrong turns and dead ends: ‘We appreciate what you’re trying to do’. Our first challenge‘s winning entry in this category was PiCymru’s We Shall Overcomb:

PiCymru : Make us Laugh Challenge

The video of the PiCymru teams Pioneer challenge entry! The team wasn’t able to get things to work the way they hoped, but wanted to share the joy of failure 🙂

The category name was suggested by our lovely judge from the first cycle, stand-up comedian Bec Hill: it’s one of the accepted heckles the audience can shout out at her stand-up scratch nights. Scratch nights are preview events at which a comedian tests new material, and they are allowed to fail on stage. We may not often think of comedy as embracing failure, but comedians do scratch nights specifically to learn from their mistakes, and to make the final product all the better for it. Interestingly, scratch nights are hugely popular with audiences.

So, if you’re working with a group of young people, what can you do to encourage learning from failure and not let them give up?

Helping you to fail better

In our book Ideas start here, for Pioneers mentors, we’ve given a few tips and phrases that can come in useful. For example, if someone says, “It isn’t working!”, you could respond with “Why not? Have you read the error log?” RTFM is a real thing, and an important skill for digital life.

We agree with engineer Prof Danielle George, who believes in being honest about your failures and highlighting their importance to where you’ve got now. “I fail a lot,” she says. “The trick is to embrace these failures; we don’t have to succeed the first time. We learn from our mistakes and move forwards.”

If, as a mentor, you’re not sure how to encourage and support those not used to failing, this article also has some more tips.

If nothing else helps, but you need to feel inspired, think about what someone said to Karen, who sucks at surfing:

Karen, you are actually pretty good at surfing. Keep in mind that billions of other humans wouldn’t dare even try.

How about you? If you have a story of what you learned from failure in one of your projects, share it in the comments!

Mistakes GIF – Find & Share on GIPHY

Discover & Share this Mistakes GIF with everyone you know. GIPHY is how you search, share, discover, and create GIFs.

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Cliché: Security through obscurity (again)

Post Syndicated from Robert Graham original http://blog.erratasec.com/2016/10/cliche-security-through-obscurity-again.html

This post keeps popping up in my timeline. It’s wrong. The phrase “security through/by security” has become such a cliché that it’s lost all meaning. When somebody says it, they are almost certainly saying a dumb thing, regardless if they support it or are trying to debunk it.

Let’s go back to first principles, namely Kerckhoff’s Principle from the 1800s that states cryptography should be secure even if everything is known about it except the key. In other words, there exists no double-secret military-grade encryption with secret algorithms. Today’s military crypto is public crypto.

Let’s apply this to port knocking. This is not a layer of obscurity, as proposed by the above post, but a layer of security. Applying Kerkhoff’s Principle, it should work even if everything is known about the port knocking algorithm except the sequence of ports being knocked.

Kerkhoff’s Principle is based on a few simple observations. Two relevant ones today are:

* things are not nearly as obscure as you think
* obscurity often impacts your friends more than your enemies

I (as an attacker) know that many sites use port knocking. Therefore, if I get no response from an IP address (which I have reason to know exists), then I’ll assume port knocking is hiding it. I know which port knocking techniques are popular. Or, sniffing at the local Starbucks, I might observe outgoing port knocking behavior, and know which sensitive systems I can attack later using the technique. Thus, though port knocking makes it look like a system doesn’t exist, this doesn’t fully hide a system from me. The security of the system should not rest on this obscurity.

Instead of an obscurity layer, port knocking a security layer. The security it provides is that it drives up the amount of effort an attacker needs to hack the system. Some use the opposite approach, whereby the firewall in front of a subnet responds with a SYN-ACK to every SYN. This likewise increases the costs of those doing port scans (like myself, who masscans the entire Internet), by making it look that all IP addresses and ports exist, not by hiding systems behind a layer of obscurity.

One plausible way of defeating a port knocking implementation is to simply scan all 64k ports many times. If you are looking for a sequence of TCP ports 1000, 5000, 2000, 4000, then you’ll see this sequence. You’ll see all sequences.

If the code for your implementation is open, then it’s easy for others to see this plausible flaw and point it out to you. You could fix this flaw by then forcing the sequence to reset every time it saw the first port, or to also listen for bad ports (ones not part of the sequence) that would likewise reset the sequence.

If your code is closed, then your friends can’t see this problem. But your enemies are still highly motivated. They might find your code, find the compiled implementation, or must just guess ways around your possible implementation. The chances that you, some random defender, is better at this than the combined effort of all your attackers is very small. Opening things up to your friends gives you a greater edge to combat your enemies.

Thus, applying Kerkoff’s Principle to this problem is that you shouldn’t rely upon the secrecy of your port knocking algorithm, or the fact that you are using port knocking in the first place.

The above post also discusses ssh on alternate ports. It points out that if an 0day is found in ssh, those who run the service on the default port of 22 will get hacked first, while those who run at odd ports, like 7837, will have time to patch their services before getting owned.

But this is just repeating the fallacy. It’s focusing only on the increase in difficulty to attackers, but ignoring the increase in difficulties to friends. Let’s say some new ssh 0day is announced. Everybody is going to rush to patch their servers. They are going to run tools like my masscan to quickly find everything listening on port 22, or a vuln scanner like Nessus. Everything on port 22 will quickly get patched. SSH servers running on port 7837, however, will not get patched. On the other other hand, Internet-wide scans like Shodan or the 2012 Internet Census may have already found that you are running ssh on port 7837. That means the attackers can quickly attack it with the latest 0day even while you, the defender, are slow to patch it.

Running ssh on alternate ports is certainly useful because, as the article points out, it dramatically cuts down on the noise that defenders have to deal with. If somebody is brute forcing passwords on port 7837, then that’s a threat worth paying more attention to than somebody doing the same at port 22. But this benefit is separate discussion from obscurity. Hiding an ssh server on an obscure port may thus be a good idea, but not because there is value to obscurity.

Thus, both port knocking and putting ssh on alternate ports are valid security strategies. However, once you mention the cliche “security by/through obscurity”, you add nothing useful to the mix.

Update: Response here.