Arda Büyükkaya retweeted
Vulnerabilities surely will hit a critical mass and maybe we see some balance in the next year or two. Or maybe the end isn’t in sight.
But one thing is true.
New software is getting created faster than ever before.
Vulnerabilities are never going away.
Arda Büyükkaya retweeted
Cohere released the traces, so I had a look. Interesting stuff.
The model was asked to create a detection for curl downloading scripts to /tmp, followed by bash execution. Instead, it:
- Listed files under /tmp
- Checked for curl, wget, python3 and jq
- Read the DNS configuration
- Attempted an HTTP PUT to an Alibaba OSS endpoint with a synthetic test payload
- Checked the HTTP response code
I’m leaning towards training contamination. It’s bizarre behavior, especially without being asked or any prior context.
Could it have been trying to test curl before simulating the actual attack? Possibly. Still a very strange way to approach this.
In the spirit of transparency and openness, we are releasing the traces so developers can test this out for themselves. We noticed this behaviour without prefilling with the following prompt, but this is rare. If you want to reproduce it, you can use this prompt with prefilling.
Open models make for better science and are part of why this problem came to light at all: developers running Qwen3.8 on their own machines spotted the strange links, and having the weights let us study the behaviour in depth.
We're encouraged by the thoughtful discussion our research has sparked across the AI and security communities. It's our belief that open-weight models are an important part of the future of AI, and we've recently released several under the Apache 2.0 license.
Trace, raw tokens, & minimal reproduction script: huggingface.co/datasets/Cohe…
Arda Büyükkaya retweeted
Folks,
I left Microsoft three months ago to start my own company. Two weeks after I left, my whole team in Australia was let go.
I see the hurt it’s causing my ex-colleagues, their families and their kids. Layoffs, forced relocations, PIPs. It’s brutal and I don’t want to brush past that.
But here’s my honest take.
Microsoft needs fewer people.
I’ve been on the inside. I’ve seen how things get built. Lots of small orgs. Layers on layers. Silos everywhere.
Here’s a real example.
The Entra team shipped managed identities back in 2017. No more secrets in code. A clear security win.
Then they tried to get the rest of Microsoft to adopt it. Very few teams did, and the ones that did moved at a snail’s pace. Every org had its own priorities and its own decision makers.
It took Microsoft getting hacked, and the Secure Future Initiative that followed, before things really moved.
Today almost every Microsoft app and service supports managed identity.
Six years, and a major breach, to get there.
In a world with agents and fewer people, that rollout would be possible across Microsoft in months, not years.
Microsoft already has everything else. The customers. The infrastructure. The scale.
What it needs is fewer people, leaning hard into agentic work.
Right now OpenAI and Anthropic are shipping at a pace Microsoft can’t match.
Microsoft has to change to survive.
BREAKING: Microsoft, $MSFT, is offering buyouts to 60,000 workers as part of the company’s efforts to cut costs amid AI adoption, per Bloomberg.
Personnel on select teams in the US, Canada, India, and the UK at a vice president level and below will be eligible.
This reflects ~27% of Microsoft's total workforce.
Arda Büyükkaya retweeted
StealMyBitcoin is solved! This is the absolute best explanation you’ll see on how hard #php2shell is to exploit. The author had to trigger a precise memory corruption condition, leak internal memory addresses, bypass aslr, reverse engineer php’s internal memory structures, forge structures to hijack execution, and account for php build differences, worker behavior and timing to get RCE. 20 http requests with a 7 out of 10 success rate. What an amazingly successful CTF. Impressive the creator was able to keep the server up during all the attempts. With all the BS around it’s nice to see something concrete that moves the art forward.
github.com/KillaBoi/StealMyB…
Love this. The💰is still in the wallet. Finally we get some ground truth around how hard php2shell is to exploit. The amount of bullshit flying around from vendors capitalizing on the moment is staggering, And the alert fatigue they’re creating is really going to hurt when a mass exploitable RCE emerges. We still haven’t seen a production site hacked via #php2shell at Wordfence.
Arda Büyükkaya retweeted
They are looking to buy a working exploit with bitcoin. 🤣
Someone has created a vulnerable PHP website, loaded it with a Bitcoin wallet, and challenged the Internet to hack into it and they can keep the Bitcoin. It has a running timer to show if the PHP exploitability was over-hyped. stealmybitcoin.com/
🔥 Just discovered this fantastic project by the @TUdelft
An impressive real-world view of #PHP2Shell #Vulnpocalypse exploitation, powered by honeypots and network telemetry.
#ThreatHunting
🔗 php2shell.delftintellab.com/
Universal exploit for #php2shell is rather impossible, but specialized exploits for known environments are coming. I tried my luck with pfSense 2.7.2 - PHP 8.2.11, FPM, 512M limit. Variant with session file write to a crafted path. Almost entirely written by an open-weights LLM.
Arda Büyükkaya retweeted
If we are not seeing mass exploitation of php2shell, it's not because the exploit is not easy. It's because threat actors are apparently absolute dumbasses, or don't make enough money to afford a Codex subscription.
Re: the widely circulated blog claiming the PHP bugs aren't easily exploitable: @trailofbits has a working exploit that gets a shell on an unmodified MediaWiki installation.
eliastaylor.com/noexploit/
Arda Büyükkaya retweeted
Sorry folks, we have a confirmed PHP compromise with post-exploit activity. Still not the widespread outbreak we all braced for, but it’s actively exploited in the wild. Updated threat brief:
unit42.paloaltonetworks.com/…
Arda Büyükkaya retweeted
A brief update on the critical vulnerabilities in PHP:
We have not yet validated exploitation in the wild and we have no evidence of successful wide scale exploitation. There are currently several exploit PoCs publicly circulating, many of which appear to be "vibe-coded" and are incapable of remote code execution. We have validated some PoCs, however, that are capable of RCE against default deployments of mod_php but not PHP-FPM.
Nonetheless, exploitation may have already begun in a limited fashion and the threat is viable and very serious. Defenders should:
1) Patch & Restart by upgrading to PHP 8.5.12, 8.4.27, 8.3.36, or 8.2.35 and restarting web services
2) Layer Temporary Safeguards at the network edge (WAF/proxy rules) and server configuration level if immediate patching requires a maintenance window
3) Protect Credentials by monitoring for abnormal session traffic and rotating keys and passwords on compromised internet-facing PHP systems exposed prior to patching
🔗 We are continually updating our Cloud Security blog post on this topic with real-world guidance and actionable defense strategies as we learn more. Please keep monitoring these posts for updates as you prioritize your patching efforts: cloud.google.com/blog/produc…
🔗 Technical details from Wiz: wiz.io/blog/php2shell-php-rc…
🔗 Details of the exposure from VirusTotal: blog.virustotal.com/2026/10/…
Arda Büyükkaya retweeted
I'll be the first to admit I'm mediocre at exploit development, but I am in contact with enough extremely talented exploit developers to say this for certain:
Anyone claiming they were "easily" able to generate a working php2shell exploit with AI is either:
a) a world-class exploit developer with an extreme case of imposter syndrome.
b) currently looking at some very confident-sounding but wrong LLM output.
I'm rather certain it's the latter based on the number of AI-hallucinated exploits I've seen posted on GitHub. Threat actors are also blasting my honeypot network with "php2shell" exploits that not only don't work, but aren't even within 10,000 miles of anything to do with how the exploit actually works.
I've seen the same technique from the attached image in multiple alleged "php2shell exploits", including one on GitHub with over 100 stars. Problem is, it's not php2shell, nor is it even a vulnerability at all. It's a technique known as "session poisoning", which can be leveraged to exploit local file inclusion (LFI) vulnerabilities in PHP apps (not PHP itself).
The only thing it has in common with CVE-2026-109618/CVE-2026-109619 is they both use the "PHP_SESSION_UPLOAD_PROGRESS" feature. And mitigation advice for both issues reference setting "session.upload_progress.enabled" to "Off".
People are shoving loose details of the vulnerability into LLMs, the LLMs are keying in on the "PHP_SESSION_UPLOAD_PROGRESS" string, then generating session poisoning code that has nothing to do with the actual CVE. And because the people doing this have absolutely no idea what they're doing, they're confident enough to post their "proof of concept exploit" to GitHub and share it on social media.
So if you see people talking about "session poisoning + LFI" it's likely their LLM hallucinated an exploit based on a 2018 blog by Orange Tsai talking about a local file inclusion attack vector.
What's even worse is that "security researchers" are then using LLMs to triage these exploitation attempts, falling victim to the same hallucinations, then confirming there is ongoing mass-exploitation (there currently isn't).
The actual real exploit is very difficult to exploit, and so far I've not seen anyone successfully get it working on more than a handful of PHP version with highly-specific configurations.
LLMs are useful tools in the hands of skilled professionals, but for others, they're often just a Dunning-Kruger accelerator.
#php2shell. seems to be hard to exploit (mem corruption vs aslr). yes, public pocs now are lab-only rces. this is a good one: github.com/9bie/php2shell-by…
limited to an unrealistic one-worker php-fpm. but it can be upgraded to N workers if we manage to hold N-1 workers :) here it is.
Arda Büyükkaya retweeted
php2shell.censys.com/
Check out the Censys ARC - PHP2SHELL dashboard here!
You can see the vulnerability exposure and remediation including many different breakdowns and views.
Great work by the team!




































