Bas Westerbaan retweeted
> The revoked intermediates themselves have no customer impact. They never issued a certificate, so no certificate in use anywhere relied on them.
This is a listed company whose business is digital signatures, completely missing the point. 🤦♂️
Everyone who either had emudhra's certs in their trust store or communicates with such entities who had that, is impacted - not just emudhra "customers". Because many web browsers, operating systems, and cloud provides included these, almost everyone in the world is impacted.
Cloudflare explains the seriousness of the problem:
Global TLS Intermediate CA incident: We’ve updated our incident page with how it happened, who is affected (one US customer ecosystem), what’s not affected, and what we’re putting in place. We will publish the root cause once our investigation is complete.
👉emudhra.com/en/post/certific…
Readers added context they thought people might want to know
eMudhra minimizes the scope by claiming only "one US customer ecosystem" is affected. In reality, 8 of its CA certificates had catastrophically weak private keys (one being simply the number 4), allowing anyone to forge trusted HTTPS certificates for any website on the internet.blog.google/security/prote…
Bas Westerbaan retweeted
Two classes extremely bad cyber vulnerabilities disclosed in the last 24 hours. The first potentially impacts everyone online. The second impacts nearly everyone running a server.
tl;dr: Everyone should upgrade their OS and Browser as soon as possible. If you run a server you should upgrade PHP (or ensure it’s removed if you’re not using it) as soon as possible.
The first class of vulnerabilities is a set of root TLS certificates that were discovered to have a trivial private key. Literally the number 4. These roots were controlled by #eMudhra. The problem is that with that an attacker could create a certificate and, if they could get in the traffic flow, intercept traffic to any site or service. The solution is to stop trusting certificates issued by these vulnerable roots. Upgrading your browser and OS is the fastest way for most Internet users to do this.
The second class of vulnerabilities doesn’t apply to most consumers directly, but does apply to most anyone running a server. These vulnerabilities have been dubbed #php2shell. PHP is one of the most widely used web programming languages. It’s estimated 70% of websites run on PHP. These vulnerabilities allow an attacker to send a crafted set of queries to a server running PHP and potentially take over the server. From there they could potentially read, modify, delete, or repurpose anything on the server. The solution is to upgrade PHP to the latest version ASAP. Even if you’re not using PHP for your web development, it’s often included by default. So make sure it is either upgraded or fully removed.
@Cloudflare received advanced warning of both of these classes of vulnerabilities. We’ve ensured that where we act as a proxy we are no longer trusting the vulnerable roots. We are also reviewing certificate transparency (CT) logs for any sign the vulnerability was exploited before its disclosure. We have not found any evidence but CT logs are not perfect and a sophisticated attacker who knew about the weakness could have exploited it without a new certificate being logged.
For the PHP vulnerabilities, we have deployed mitigations available for all customers for free. Because of the complexity of the vulnerabilities and number of ways it can be exploited, we also released new WAF capabilities that are unique in the industry to catch the exploit based on the response. These too are available for every Cloudflare customer for free.
Even if you are taking advantage of Cloudflare’s protection, it is important to upgrade your OS, browsers, and PHP installations as soon as possible. We can provide a strong bandaid, but the best protection is to fix the underlying problem.
If you’re interested in learning more, you can read our blogs:
Vulnerable roots: blog.cloudflare.com/emudhra-…
PHP vulnerabilities: blog.cloudflare.com/php-vuln…
Bas Westerbaan retweeted
PHP sites behind Cloudflare already have an initial set of WAF rules deployed for the known exploit vectors in these vulnerabilities. The rules are available to all customers, including free.
We are seeing early attacks emerging and are updating mitigations as new vectors show up.
This is a STOPGAP only. Patch as soon as @ThePHPF releases the update at 14:00 UTC today.
Bas Westerbaan retweeted
Following the discovery that eight eMudhra intermediate certificates use weak keys, Cloudflare is deploying mitigations and releasing client updates. We explain the impact, our response, and what customers and developers should do next. cfl.re/487DNbG
Bas Westerbaan retweeted
Except when it wasn’t and turns out brought to you by the #4 . Big thanks to everyone working to make us safer last 24 hours. imgs.xkcd.com/comics/random_…
Internet Security starts with randomness… atlasobscura.com/videos/thes…
Bas Westerbaan retweeted
CLAUDE FOUND THE SEEDS
anthropic.com/research/ecdsa…
Bas Westerbaan retweeted
CLAUDE FOUND THE SEEDS
anthropic.com/research/ecdsa…
Bas Westerbaan retweeted
Can you build blind signatures from ML-DSA? Yes of course you can! But what will the performance be?
In recent work, we looked at the efficiency of Non-Interactive Zero-Knowledge proofs of knowledge of an ML-DSA signature.
Bas Westerbaan retweeted
yikes: via HDNL 1 Shor "only" gets to you to decrypt one secure channel session, whereas 1 Shor'd PKI cert or auth cert/token can get you access to a whole network/org (modulo the detection heuristics and other auth factors etc.)
Indeed. There is a best algorithm to break RSA-2048 that only God knows. It might be classical or quantum. The quantum one is practical. We hope the classical one isn't. AI helps us answer that question faster. AI doesn't break cryptography: it lets us know it was broken faster.
"discrete log is just like a math conjecture, it's a matter of time and tokens"
No. AI may optimize the best known algorithms and/or implementations, but if factoring/DL are hard (although not NP-complete, if P!=NP we know such hard "NP-intermediate" exist), then no efficient solver exists, ergo no AI can find one. Most likely P!=NP.
< insert caveats about worst/average-case hardness>
Bas Westerbaan retweeted
This is what I have been telling everyone who will listen.
The most valuable thing the frontier labs can now do for crypto (and math more broadly) is publish their *negative* results. What ideas they tried, how much compute they used, and what obstacles they found.
Bas Westerbaan retweeted
new Keccak variant: MiniSHAKE
800-bit permutation (instead of 1600), only 12 rounds (instead of 24), great idea!
eprint.iacr.org/2026/2363
Bas Westerbaan retweeted
I'm pretty sure that if have AI and even half-competent people using it -- with high likelihood you will find exploitable issues in the "Type A" equivalents of any country. Good news if your intelligence op is a bit short-staffed on the "top-secret cleared math genius" dept..