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Apple is bowing to pressure from the Chinese government and storing encryption keys in China. While I would prefer it if it would take a stand against China, I really can’t blame it for putting its business model ahead of its desires for customer privacy.
The National Academies has just published “Decrypting the Encryption Debate: A Framework for Decision Makers.” It looks really good, although I have not read it yet.
Not much news or analysis yet. Please post any links you find in the comments, and I will summarize them here.
In “The House that Spied on Me,” Kashmir Hill outfits her home to be as “smart” as possible and writes about the results.
A new vulnerability in WhatsApp has been discovered:
…the researchers unearthed far more significant gaps in WhatsApp’s security: They say that anyone who controls WhatsApp’s servers could effortlessly insert new people into an otherwise private group, even without the permission of the administrator who ostensibly controls access to that conversation.
Matthew Green has a good description:
If all you want is the TL;DR, here’s the headline finding: due to flaws in both Signal and WhatsApp (which I single out because I use them), it’s theoretically possible for strangers to add themselves to an encrypted group chat. However, the caveat is that these attacks are extremely difficult to pull off in practice, so nobody needs to panic. But both issues are very avoidable, and tend to undermine the logic of having an end-to-end encryption protocol in the first place.
Here’s the research paper.
EDITED TO ADD (2/12): Commentary from Moxie Marlinspike, the developer of the protocol.
No More Ransom is a central repository of keys and applications for ransomware, so people can recover their data without paying. It’s not complete, of course, but is pretty good against older strains of ransomware. The site is a joint effort by Europol, the Dutch police, Kaspersky, and McAfee.
Deputy Attorney General Rosenstein has given talks where he proposes that tech companies decrease their communications and device security for the benefit of the FBI. In a recent talk, his idea is that tech companies just save a copy of the plaintext:
Law enforcement can also partner with private industry to address a problem we call “Going Dark.” Technology increasingly frustrates traditional law enforcement efforts to collect evidence needed to protect public safety and solve crime. For example, many instant-messaging services now encrypt messages by default. The prevent the police from reading those messages, even if an impartial judge approves their interception.
The problem is especially critical because electronic evidence is necessary for both the investigation of a cyber incident and the prosecution of the perpetrator. If we cannot access data even with lawful process, we are unable to do our job. Our ability to secure systems and prosecute criminals depends on our ability to gather evidence.
I encourage you to carefully consider your company’s interests and how you can work cooperatively with us. Although encryption can help secure your data, it may also prevent law enforcement agencies from protecting your data.
Encryption serves a valuable purpose. It is a foundational element of data security and essential to safeguarding data against cyber-attacks. It is critical to the growth and flourishing of the digital economy, and we support it. I support strong and responsible encryption.
I simply maintain that companies should retain the capability to provide the government unencrypted copies of communications and data stored on devices, when a court orders them to do so.
Responsible encryption is effective secure encryption, coupled with access capabilities. We know encryption can include safeguards. For example, there are systems that include central management of security keys and operating system updates; scanning of content, like your e-mails, for advertising purposes; simulcast of messages to multiple destinations at once; and key recovery when a user forgets the password to decrypt a laptop. No one calls any of those functions a “backdoor.” In fact, those very capabilities are marketed and sought out.
I do not believe that the government should mandate a specific means of ensuring access. The government does not need to micromanage the engineering.
The question is whether to require a particular goal: When a court issues a search warrant or wiretap order to collect evidence of crime, the company should be able to help. The government does not need to hold the key.
Rosenstein is right that many services like Gmail naturally keep plaintext in the cloud. This is something we pointed out in our 2016 paper: “Don’t Panic.” But forcing companies to build an alternate means to access the plaintext that the user can’t control is an enormous vulnerability.
The German Interior Minister is preparing a bill that allows the government to mandate backdoors in encryption.
No details about how likely this is to pass. I am skeptical.
It’s a lot more chemistry than I understand:
Invisible inks based on “smart” fluorescent materials have been shining brightly (if only you could see them) in the data-encryption/decryption arena lately…. But some of the materials are costly or difficult to prepare, and many of these inks remain somewhat visible when illuminated with ambient or ultraviolet light. Liang Li and coworkers at Shanghai Jiao Tong University may have come up with a way to get around those problems. The team prepared a colorless solution of an inexpensive lead-based metal-organic framework (MOF) compound and used it in an ink-jet printer to create completely invisible patterns on paper. Then they exposed the paper to a methylammonium bromide decryption solution…revealing the pattern…. They rendered the pattern invisible again by briefly treating the paper with a polar solvent….
Full paper.
Earlier this month, Deputy Attorney General Rod Rosenstein gave a speech warning that a world with encryption is a world without law—or something like that. The EFF’s Kurt Opsahl takes it apart pretty thoroughly.
Last week, FBI Director Christopher Wray said much the same thing.
This is an idea that will not die.
Mathy Vanhoef has just published a devastating attack against WPA2, the 14-year-old encryption protocol used by pretty much all Wi-Fi systems. It’s an interesting attack, where the attacker forces the protocol to reuse a key. The authors call this attack KRACK, for Key Reinstallation Attacks.
This is yet another of a series of marketed attacks; with a cool name, a website, and a logo. The Q&A on the website answers a lot of questions about the attack and its implications. And lots of good information in this ArsTechnica article.
There is an academic paper, too:
“Key Reinstallation Attacks: Forcing Nonce Reuse in WPA2,” by Mathy Vanhoef and Frank Piessens.
Abstract: We introduce the key reinstallation attack. This attack abuses design or implementation flaws in cryptographic protocols to reinstall an already-in-use key. This resets the key’s associated parameters such as transmit nonces and receive replay counters. Several types of cryptographic Wi-Fi handshakes are affected by the attack. All protected Wi-Fi networks use the 4-way handshake to generate a fresh session key. So far, this 14-year-old handshake has remained free from attacks, and is even proven secure. However, we show that the 4-way handshake is vulnerable to a key reinstallation attack. Here, the adversary tricks a victim into reinstalling an already-in-use key. This is achieved by manipulating and replaying handshake messages. When reinstalling the key, associated parameters such as the incremental transmit packet number (nonce) and receive packet number (replay counter) are reset to their initial value. Our key reinstallation attack also breaks the PeerKey, group key, and Fast BSS Transition (FT) handshake. The impact depends on the handshake being attacked, and the data-confidentiality protocol in use. Simplified, against AES-CCMP an adversary can replay and decrypt (but not forge) packets. This makes it possible to hijack TCP streams and inject malicious data into them. Against WPA-TKIP and GCMP the impact is catastrophic: packets can be replayed, decrypted, and forged. Because GCMP uses the same authentication key in both communication directions, it is especially affected.
Finally, we confirmed our findings in practice, and found that every Wi-Fi device is vulnerable to some variant of our attacks. Notably, our attack is exceptionally devastating against Android 6.0: it forces the client into using a predictable all-zero encryption key.
I’m just reading about this now, and will post more information as I learn it.
EDITED TO ADD: This meets my definition of brilliant. The attack is blindingly obvious once it’s pointed out, but for over a decade no one noticed it.
EDITED TO ADD: Matthew Green has a blog post on what went wrong. The vulnerability is in the interaction between two protocols. At a meta level, he blames the opaque IEEE standards process:
One of the problems with IEEE is that the standards are highly complex and get made via a closed-door process of private meetings. More importantly, even after the fact, they’re hard for ordinary security researchers to access. Go ahead and google for the IETF TLS or IPSec specifications—you’ll find detailed protocol documentation at the top of your Google results. Now go try to Google for the 802.11i standards. I wish you luck.
The IEEE has been making a few small steps to ease this problem, but they’re hyper-timid incrementalist bullshit. There’s an IEEE program called GET that allows researchers to access certain standards (including 802.11) for free, but only after they’ve been public for six months—coincidentally, about the same time it takes for vendors to bake them irrevocably into their hardware and software.
This whole process is dumb and—in this specific case—probably just cost industry tens of millions of dollars. It should stop.
Nicholas Weaver explains why most people shouldn’t worry about this:
So unless your Wi-Fi password looks something like a cat’s hairball (e.g. “:SNEIufeli7rc”—which is not guessable with a few million tries by a computer), a local attacker had the capability to determine the password, decrypt all the traffic, and join the network before KRACK.
KRACK is, however, relevant for enterprise Wi-Fi networks: networks where you needed to accept a cryptographic certificate to join initially and have to provide both a username and password. KRACK represents a new vulnerability for these networks. Depending on some esoteric details, the attacker can decrypt encrypted traffic and, in some cases, inject traffic onto the network.
But in none of these cases can the attacker join the network completely. And the most significant of these attacks affects Linux devices and Android phones, they don’t affect Macs, iPhones, or Windows systems. Even when feasible, these attacks require physical proximity: An attacker on the other side of the planet can’t exploit KRACK, only an attacker in the parking lot can.
EDITED TO ADD (11/13): The official link to the paper blocks anonymous users. Here’s an alternate.
Sidebar photo of Bruce Schneier by Joe MacInnis.