Tag Archives: NSA

On the Subversion of NIST by the NSA

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2022/06/on-the-subversion-of-nist-by-the-nsa.html

Nadiya Kostyuk and Susan Landau wrote an interesting paper: “Dueling Over DUAL_EC_DRBG: The Consequences of Corrupting a Cryptographic Standardization Process“:

Abstract: In recent decades, the U.S. National Institute of Standards and Technology (NIST), which develops cryptographic standards for non-national security agencies of the U.S. government, has emerged as the de facto international source for cryptographic standards. But in 2013, Edward Snowden disclosed that the National Security Agency had subverted the integrity of a NIST cryptographic standard­the Dual_EC_DRBG­enabling easy decryption of supposedly secured communications. This discovery reinforced the desire of some public and private entities to develop their own cryptographic standards instead of relying on a U.S. government process. Yet, a decade later, no credible alternative to NIST has emerged. NIST remains the only viable candidate for effectively developing internationally trusted cryptography standards.

Cryptographic algorithms are essential to security yet are hard to understand and evaluate. These technologies provide crucial security for communications protocols. Yet the protocols transit international borders; they are used by countries that do not necessarily trust each other. In particular, these nations do not necessarily trust the developer of the cryptographic standard.

Seeking to understand how NIST, a U.S. government agency, was able to remain a purveyor of cryptographic algorithms despite the Dual_EC_DRBG problem, we examine the Dual_EC_DRBG situation, NIST’s response, and why a non-regulatory, non-national security U.S. agency remains a successful international supplier of strong cryptographic solutions.

The NSA Says that There are No Known Flaws in NIST’s Quantum-Resistant Algorithms

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2022/05/the-nsa-says-that-there-are-no-known-flaws-in-nists-quantum-resistant-algorithms.html

Rob Joyce, the director of cybersecurity at the NSA, said so in an interview:

The NSA already has classified quantum-resistant algorithms of its own that it developed over many years, said Joyce. But it didn’t enter any of its own in the contest. The agency’s mathematicians, however, worked with NIST to support the process, trying to crack the algorithms in order to test their merit.

“Those candidate algorithms that NIST is running the competitions on all appear strong, secure, and what we need for quantum resistance,” Joyce said. “We’ve worked against all of them to make sure they are solid.”

The purpose of the open, public international scrutiny of the separate NIST algorithms is “to build trust and confidence,” he said.

I believe him. This is what the NSA did with NIST’s candidate algorithms for AES and then for SHA-3. NIST’s Post-Quantum Cryptography Standardization Process looks good.

I still worry about the long-term security of the submissions, though. In 2018, in an essay titled “Cryptography After the Aliens Land,” I wrote:

…there is always the possibility that those algorithms will fall to aliens with better quantum techniques. I am less worried about symmetric cryptography, where Grover’s algorithm is basically an upper limit on quantum improvements, than I am about public-key algorithms based on number theory, which feel more fragile. It’s possible that quantum computers will someday break all of them, even those that today are quantum resistant.

It took us a couple of decades to fully understand von Neumann computer architecture. I’m sure it will take years of working with a functional quantum computer to fully understand the limits of that architecture. And some things that we think of as computationally hard today will turn out not to be.

Details of an NSA Hacking Operation

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2022/03/details-of-an-nsa-hacking-operation.html

Pangu Lab in China just published a report of a hacking operation by the Equation Group (aka the NSA). It noticed the hack in 2013, and was able to map it with Equation Group tools published by the Shadow Brokers (aka some Russian group).

…the scope of victims exceeded 287 targets in 45 countries, including Russia, Japan, Spain, Germany, Italy, etc. The attack lasted for over 10 years. Moreover, one victim in Japan is used as a jump server for further attack.

News article.

Interview with the Head of the NSA’s Research Directorate

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2022/02/interview-with-the-head-of-the-nsas-research-directorate.html

MIT Technology Review published an interview with Gil Herrera, the new head of the NSA’s Research Directorate. There’s a lot of talk about quantum computing, monitoring 5G networks, and the problems of big data:

The math department, often in conjunction with the computer science department, helps tackle one of NSA’s most interesting problems: big data. Despite public reckoning over mass surveillance, NSA famously faces the challenge of collecting such extreme quantities of data that, on top of legal and ethical problems, it can be nearly impossible to sift through all of it to find everything of value. NSA views the kind of “vast access and collection” that it talks about internally as both an achievement and its own set of problems. The field of data science aims to solve them.

“Everyone thinks their data is the messiest in the world, and mine maybe is because it’s taken from people who don’t want us to have it, frankly,” said Herrera’s immediate predecessor at the NSA, the computer scientist Deborah Frincke, during a 2017 talk at Stanford. “The adversary does not speak clearly in English with nice statements into a mic and, if we can’t understand it, send us a clearer statement.”

Making sense of vast stores of unclear, often stolen data in hundreds of languages and even more technical formats remains one of the directorate’s enduring tasks.

More Military Cryptanalytics, Part III

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2021/08/more-military-cryptanalytics-part-iii.html

Late last year, the NSA declassified and released a redacted version of Lambros D. Callimahos’s Military Cryptanalytics, Part III. We just got most of the index. It’s hard to believe that there are any real secrets left in this 44-year-old volume.

Chinese Hackers Stole an NSA Windows Exploit in 2014

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2021/03/chinese-hackers-stole-an-nsa-windows-exploit-in-2014.html

Check Point has evidence that (probably government affiliated) Chinese hackers stole and cloned an NSA Windows hacking tool years before (probably government affiliated) Russian hackers stole and then published the same tool. Here’s the timeline:

The timeline basically seems to be, according to Check Point:

  • 2013: NSA’s Equation Group developed a set of exploits including one called EpMe that elevates one’s privileges on a vulnerable Windows system to system-administrator level, granting full control. This allows someone with a foothold on a machine to commandeer the whole box.
  • 2014-2015: China’s hacking team code-named APT31, aka Zirconium, developed Jian by, one way or another, cloning EpMe.
  • Early 2017: The Equation Group’s tools were teased and then leaked online by a team calling itself the Shadow Brokers. Around that time, Microsoft cancelled its February Patch Tuesday, identified the vulnerability exploited by EpMe (CVE-2017-0005), and fixed it in a bumper March update. Interestingly enough, Lockheed Martin was credited as alerting Microsoft to the flaw, suggesting it was perhaps used against an American target.
  • Mid 2017: Microsoft quietly fixed the vulnerability exploited by the leaked EpMo exploit.

Lots of news articles about this.

Military Cryptanalytics, Part III

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2021/01/military-cryptanalytics-part-iii.html

The NSA has just declassified and released a redacted version of Military Cryptanalytics, Part III, by Lambros D. Callimahos, October 1977.

Parts I and II, by Lambros D. Callimahos and William F. Friedman, were released decades ago — I believe repeatedly, in increasingly unredacted form — and published by the late Wayne Griswold Barker’s Agean Park Press. I own them in hardcover.

Like Parts I and II, Part III is primarily concerned with pre-computer ciphers. At this point, the document only has historical interest. If there is any lesson for today, it’s that modern cryptanalysis is possible primarily because people make mistakes

The monograph took a while to become public. The cover page says that the initial FOIA request was made in July 2012: eight and a half years ago.

And there’s more books to come. Page 1 starts off:

This text constitutes the third of six basic texts on the science of cryptanalytics. The first two texts together have covered most of the necessary fundamentals of cryptanalytics; this and the remaining three texts will be devoted to more specialized and more advanced aspects of the science.

Presumably, volumes IV, V, and VI are still hidden inside the classified libraries of the NSA.

And from page ii:

Chapters IV-XI are revisions of seven of my monographs in the NSA Technical Literature Series, viz: Monograph No. 19, “The Cryptanalysis of Ciphertext and Plaintext Autokey Systems”; Monograph No. 20, “The Analysis of Systems Employing Long or Continuous Keys”; Monograph No. 21, “The Analysis of Cylindrical Cipher Devices and Strip Cipher Systems”; Monograph No. 22, “The Analysis of Systems Employing Geared Disk Cryptomechanisms”; Monograph No.23, “Fundamentals of Key Analysis”; Monograph No. 15, “An Introduction to Teleprinter Key Analysis”; and Monograph No. 18, “Ars Conjectandi: The Fundamentals of Cryptodiagnosis.”

This points to a whole series of still-classified monographs whose titles we do not even know.

EDITED TO ADD: I have been informed by a reliable source that Parts 4 through 6 were never completed. There may be fragments and notes, but no finished works.

NSA on Authentication Hacks (Related to SolarWinds Breach)

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/12/nsa-on-authentication-hacks-related-to-solarwinds-breach.html

The NSA has published an advisory outlining how “malicious cyber actors” are “are manipulating trust in federated authentication environments to access protected data in the cloud.” This is related to the SolarWinds hack I have previously written about, and represents one of the techniques the SVR is using once it has gained access to target networks.

From the summary:

Malicious cyberactors are abusing trust in federated authentication environments to access protected data. The exploitation occurs after the actors have gained initial access to a victim’s on-premises network. The actors leverage privileged access in the on-premises environment to subvert the mechanisms that the organization uses to grant access to cloud and on-premises resources and/or to compromise administrator credentials with the ability to manage cloud resources. The actors demonstrate two sets of tactics, techniques,and procedures (TTP) for gaining access to the victim network’s cloud resources, often with a particular focus on organizational email.

In the first TTP, the actors compromise on-premises components of a federated SSO infrastructure and steal the credential or private key that is used to sign Security Assertion Markup Language (SAML) tokens(TA0006, T1552, T1552.004). Using the private keys, the actors then forge trusted authentication tokens to access cloud resources. A recent NSA Cybersecurity Advisory warned of actors exploiting a vulnerability in VMware Access and VMware Identity Manager that allowed them to perform this TTP and abuse federated SSO infrastructure.While that example of this TTP may have previously been attributed to nation-state actors, a wealth of actors could be leveraging this TTP for their objectives. This SAML forgery technique has been known and used by cyber actors since at least 2017.

In a variation of the first TTP, if the malicious cyber actors are unable to obtain anon-premises signing key, they would attempt to gain sufficient administrative privileges within the cloud tenant to add a malicious certificate trust relationship for forging SAML tokens.

In the second TTP, the actors leverage a compromised global administrator account to assign credentials to cloud application service principals (identities for cloud applications that allow the applications to be invoked to access other cloud resources). The actors then invoke the application’s credentials for automated access to cloud resources (often email in particular) that would otherwise be difficult for the actors to access or would more easily be noticed as suspicious (T1114, T1114.002).

This is an ongoing story, and I expect to see a lot more about TTP — nice acronym there — in coming weeks.

Related: Tom Bossert has a scathing op-ed on the breach. Jack Goldsmith’s essay is worth reading. So is Nick Weaver’s.

Michael Ellis as NSA General Counsel

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/11/michael-ellis-as-nsa-general-counsel.html

Over at Lawfare, Susan Hennessey has an excellent primer on how Trump loyalist Michael Ellis got to be the NSA General Counsel, over the objections of NSA Director Paul Nakasone, and what Biden can and should do about it.

While important details remain unclear, media accounts include numerous indications of irregularity in the process by which Ellis was selected for the job, including interference by the White House. At a minimum, the evidence of possible violations of civil service rules demand immediate investigation by Congress and the inspectors general of the Department of Defense and the NSA.

The moment also poses a test for President-elect Biden’s transition, which must address the delicate balance between remedying improper politicization of the intelligence community, defending career roles against impermissible burrowing, and restoring civil service rules that prohibit both partisan favoritism and retribution. The Biden team needs to set a marker now, to clarify the situation to the public and to enable a new Pentagon general counsel to proceed with credibility and independence in investigating and potentially taking remedial action upon assuming office.

The NSA general counsel is not a Senate-confirmed role. Unlike the general counsels of the CIA, Pentagon and Office of the Director of National Intelligence (ODNI), all of which require confirmation, the NSA’s general counsel is a senior career position whose occupant is formally selected by and reports to the general counsel of the Department of Defense. It’s an odd setup — ­and one that obscures certain realities, like the fact that the NSA general counsel in practice reports to the NSA director. This structure is the source of a perennial legislative fight. Every few years, Congress proposes laws to impose a confirmation requirement as more appropriately befits an essential administration role, and every few years, the executive branch opposes those efforts as dangerously politicizing what should be a nonpolitical job.

While a lack of Senate confirmation reduces some accountability and legislative screening, this career selection process has the benefit of being designed to eliminate political interference and to ensure the most qualified candidate is hired. The system includes a complex set of rules governing a selection board that interviews candidates, certifies qualifications and makes recommendations guided by a set of independent merit-based principles. The Pentagon general counsel has the final call in making a selection. For example, if the panel has ranked a first-choice candidate, the general counsel is empowered to choose one of the others.

Ryan Goodman has a similar article at Just Security.

The NSA is Refusing to Disclose its Policy on Backdooring Commercial Products

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/10/the-nsa-is-refusing-to-disclose-its-policy-on-backdooring-commercial-products.html

Senator Ron Wyden asked, and the NSA didn’t answer:

The NSA has long sought agreements with technology companies under which they would build special access for the spy agency into their products, according to disclosures by former NSA contractor Edward Snowden and reporting by Reuters and others.

These so-called back doors enable the NSA and other agencies to scan large amounts of traffic without a warrant. Agency advocates say the practice has eased collection of vital intelligence in other countries, including interception of terrorist communications.

The agency developed new rules for such practices after the Snowden leaks in order to reduce the chances of exposure and compromise, three former intelligence officials told Reuters. But aides to Senator Ron Wyden, a leading Democrat on the Senate Intelligence Committee, say the NSA has stonewalled on providing even the gist of the new guidelines.

[…]

The agency declined to say how it had updated its policies on obtaining special access to commercial products. NSA officials said the agency has been rebuilding trust with the private sector through such measures as offering warnings about software flaws.

“At NSA, it’s common practice to constantly assess processes to identify and determine best practices,” said Anne Neuberger, who heads NSA’s year-old Cybersecurity Directorate. “We don’t share specific processes and procedures.”

Three former senior intelligence agency figures told Reuters that the NSA now requires that before a back door is sought, the agency must weigh the potential fallout and arrange for some kind of warning if the back door gets discovered and manipulated by adversaries.

The article goes on to talk about Juniper Networks equipment, which had the NSA-created DUAL_EC PRNG backdoor in its products. That backdoor was taken advantage of by an unnamed foreign adversary.

Juniper Networks got into hot water over Dual EC two years later. At the end of 2015, the maker of internet switches disclosed that it had detected malicious code in some firewall products. Researchers later determined that hackers had turned the firewalls into their own spy tool here by altering Juniper’s version of Dual EC.

Juniper said little about the incident. But the company acknowledged to security researcher Andy Isaacson in 2016 that it had installed Dual EC as part of a “customer requirement,” according to a previously undisclosed contemporaneous message seen by Reuters. Isaacson and other researchers believe that customer was a U.S. government agency, since only the U.S. is known to have insisted on Dual EC elsewhere.

Juniper has never identified the customer, and declined to comment for this story.

Likewise, the company never identified the hackers. But two people familiar with the case told Reuters that investigators concluded the Chinese government was behind it. They declined to detail the evidence they used.

Okay, lots of unsubstantiated claims and innuendo here. And Neuberger is right; the NSA shouldn’t share specific processes and procedures. But as long as this is a democratic country, the NSA has an obligation to disclose its general processes and procedures so we all know what they’re doing in our name. And if it’s still putting surveillance ahead of security.

NSA Advisory on Chinese Government Hacking

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/10/nsa-advisory-on-chinese-government-hacking.html

The NSA released an advisory listing the top twenty-five known vulnerabilities currently being exploited by Chinese nation-state attackers.

This advisory provides Common Vulnerabilities and Exposures (CVEs) known to be recently leveraged, or scanned-for, by Chinese state-sponsored cyber actors to enable successful hacking operations against a multitude of victim networks. Most of the vulnerabilities listed below can be exploited to gain initial access to victim networks using products that are directly accessible from the Internet and act as gateways to internal networks. The majority of the products are either for remote access (T1133) or for external web services (T1190), and should be prioritized for immediate patching.

Google Responds to Warrants for “About” Searches

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/10/google-responds-to-warrants-for-about-searches.html

One of the things we learned from the Snowden documents is that the NSA conducts “about” searches. That is, searches based on activities and not identifiers. A normal search would be on a name, or IP address, or phone number. An about search would something like “show me anyone that has used this particular name in a communications,” or “show me anyone who was at this particular location within this time frame.” These searches are legal when conducted for the purpose of foreign surveillance, but the worry about using them domestically is that they are unconstitutionally broad. After all, the only way to know who said a particular name is to know what everyone said, and the only way to know who was at a particular location is to know where everyone was. The very nature of these searches requires mass surveillance.

The FBI does not conduct mass surveillance. But many US corporations do, as a normal part of their business model. And the FBI uses that surveillance infrastructure to conduct its own about searches. Here’s an arson case where the FBI asked Google who searched for a particular street address:

Homeland Security special agent Sylvette Reynoso testified that her team began by asking Google to produce a list of public IP addresses used to google the home of the victim in the run-up to the arson. The Chocolate Factory [Google] complied with the warrant, and gave the investigators the list. As Reynoso put it:

On June 15, 2020, the Honorable Ramon E. Reyes, Jr., United States Magistrate Judge for the Eastern District of New York, authorized a search warrant to Google for users who had searched the address of the Residence close in time to the arson.

The records indicated two IPv6 addresses had been used to search for the address three times: one the day before the SUV was set on fire, and the other two about an hour before the attack. The IPv6 addresses were traced to Verizon Wireless, which told the investigators that the addresses were in use by an account belonging to Williams.

Google’s response is that this is rare:

While word of these sort of requests for the identities of people making specific searches will raise the eyebrows of privacy-conscious users, Google told The Register the warrants are a very rare occurrence, and its team fights overly broad or vague requests.

“We vigorously protect the privacy of our users while supporting the important work of law enforcement,” Google’s director of law enforcement and information security Richard Salgado told us. “We require a warrant and push to narrow the scope of these particular demands when overly broad, including by objecting in court when appropriate.

“These data demands represent less than one per cent of total warrants and a small fraction of the overall legal demands for user data that we currently receive.”

Here’s another example of what seems to be about data leading to a false arrest.

According to the lawsuit, police investigating the murder knew months before they arrested Molina that the location data obtained from Google often showed him in two places at once, and that he was not the only person who drove the Honda registered under his name.

Avondale police knew almost two months before they arrested Molina that another man ­ his stepfather ­ sometimes drove Molina’s white Honda. On October 25, 2018, police obtained records showing that Molina’s Honda had been impounded earlier that year after Molina’s stepfather was caught driving the car without a license.

Data obtained by Avondale police from Google did show that a device logged into Molina’s Google account was in the area at the time of Knight’s murder. Yet on a different date, the location data from Google also showed that Molina was at a retirement community in Scottsdale (where his mother worked) while debit card records showed that Molina had made a purchase at a Walmart across town at the exact same time.

Molina’s attorneys argue that this and other instances like it should have made it clear to Avondale police that Google’s account-location data is not always reliable in determining the actual location of a person.

“About” searches might be rare, but that doesn’t make them a good idea. We have knowingly and willingly built the architecture of a police state, just so companies can show us ads. (And it is increasingly apparent that the advertising-supported Internet is heading for a crash.)

The NSA on the Risks of Exposing Location Data

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/08/the_nsa_on_the_.html

The NSA has issued an advisory on the risks of location data.

Mitigations reduce, but do not eliminate, location tracking risks in mobile devices. Most users rely on features disabled by such mitigations, making such safeguards impractical. Users should be aware of these risks and take action based on their specific situation and risk tolerance. When location exposure could be detrimental to a mission, users should prioritize mission risk and apply location tracking mitigations to the greatest extent possible. While the guidance in this document may be useful to a wide range of users, it is intended primarily for NSS/DoD system users.

The document provides a list of mitigation strategies, including turning things off:

If it is critical that location is not revealed for a particular mission, consider the following recommendations:

  • Determine a non-sensitive location where devices with wireless capabilities can be secured prior to the start of any activities. Ensure that the mission site cannot be predicted from this location.
  • Leave all devices with any wireless capabilities (including personal devices) at this non-sensitive location. Turning off the device may not be sufficient if a device has been compromised.
  • For mission transportation, use vehicles without built-in wireless communication capabilities, or turn off the capabilities, if possible.

Of course, turning off your wireless devices is itself a signal that something is going on. It’s hard to be clandestine in our always connected world.

News articles.

NSA on Securing VPNs

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/07/nsa_on_securing.html

The NSA’s Central Security Service — that’s the part that’s supposed to work on defense — has released two documents (a full and an abridged version) on securing virtual private networks. Some of it is basic, but it contains good information.

Maintaining a secure VPN tunnel can be complex and requires regular maintenance. To maintain a secure VPN, network administrators should perform the following tasks on a regular basis:

  • Reduce the VPN gateway attack surface
  • Verify that cryptographic algorithms are Committee on National Security Systems Policy (CNSSP) 15-compliant
  • Avoid using default VPN settings
  • Remove unused or non-compliant cryptography suites
  • Apply vendor-provided updates (i.e. patches) for VPN gateways and clients

Bart Gellman on Snowden

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/05/bart_gellman_on.html

Bart Gellman’s long-awaited (at least by me) book on Edward Snowden, Dark Mirror: Edward Snowden and the American Surveillance State, will finally be published in a couple of weeks. There is an adapted excerpt in the Atlantic.

It’s an interesting read, mostly about the government surveillance of him and other journalists. He speaks about an NSA program called FIRSTFRUITS that specifically spies on US journalists. (This isn’t news; we learned about this in 2006. But there are lots of new details.)

One paragraph in the excerpt struck me:

Years later Richard Ledgett, who oversaw the NSA’s media-leaks task force and went on to become the agency’s deputy director, told me matter-of-factly to assume that my defenses had been breached. “My take is, whatever you guys had was pretty immediately in the hands of any foreign intelligence service that wanted it,” he said, “whether it was Russians, Chinese, French, the Israelis, the Brits. Between you, Poitras, and Greenwald, pretty sure you guys can’t stand up to a full-fledged nation-state attempt to exploit your IT. To include not just remote stuff, but hands-on, sneak-into-your-house-at-night kind of stuff. That’s my guess.”

I remember thinking the same thing. It was the summer of 2013, and I was visiting Glenn Greenwald in Rio de Janeiro. This was just after Greenwald’s partner was detained in the UK trying to ferry some documents from Laura Poitras in Berlin back to Greenwald. It was an opsec disaster; they would have been much more secure if they’d emailed the encrypted files. In fact, I told them to do that, every single day. I wanted them to send encrypted random junk back and forth constantly, to hide when they were actually sharing real data.

As soon as I saw their house I realized exactly what Ledgett said. I remember standing outside the house, looking into the dense forest for TEMPEST receivers. I didn’t see any, which only told me they were well hidden. I assumed black-bag teams from various countries had been all over the house when they were out for dinner, and wondered what would have happened if teams from different countries bumped into each other. I assumed that all the countries Ledgett listed above — plus the US and a few more — had a full take of what Snowden gave the journalists. These journalists against those governments just wasn’t a fair fight.

I’m looking forward to reading Gellman’s book. I’m kind of surprised no one sent me an advance copy.

Securing Internet Videoconferencing Apps: Zoom and Others

Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2020/04/secure_internet.html

The NSA just published a survey of video conferencing apps. So did Mozilla.

Zoom is on the good list, with some caveats. The company has done a lot of work addressing previous security concerns. It still has a bit to go on end-to-end encryption. Matthew Green looked at this. Zoom does offer end-to-end encryption if 1) everyone is using a Zoom app, and not logging in to the meeting using a webpage, and 2) the meeting is not being recorded in the cloud. That’s pretty good, but the real worry is where the encryption keys are generated and stored. According to Citizen Lab, the company generates them.

The Zoom transport protocol adds Zoom’s own encryption scheme to RTP in an unusual way. By default, all participants’ audio and video in a Zoom meeting appears to be encrypted and decrypted with a single AES-128 key shared amongst the participants. The AES key appears to be generated and distributed to the meeting’s participants by Zoom servers. Zoom’s encryption and decryption use AES in ECB mode, which is well-understood to be a bad idea, because this mode of encryption preserves patterns in the input.

The algorithm part was just fixed:

AES 256-bit GCM encryption: Zoom is upgrading to the AES 256-bit GCM encryption standard, which offers increased protection of your meeting data in transit and resistance against tampering. This provides confidentiality and integrity assurances on your Zoom Meeting, Zoom Video Webinar, and Zoom Phone data. Zoom 5.0, which is slated for release within the week, supports GCM encryption, and this standard will take effect once all accounts are enabled with GCM. System-wide account enablement will take place on May 30.

There is nothing in Zoom’s latest announcement about key management. So: while the company has done a really good job improving the security and privacy of their platform, there seems to be just one step remaining.

Finally — I use Zoom all the time. I finished my Harvard class using Zoom; it’s the university standard. I am having Inrupt company meetings on Zoom. I am having professional and personal conferences on Zoom. It’s what everyone has, and the features are really good.