Frontier models found the vulnerabilities. Only the attacker found the chains

What happened

Attackers don't read your repository they hit your URL, and chain together whatever they find. In an era where offensive AI runs against live applications at machine speed, your security tooling needs to go beyond finding vulnerabilities to prove exploitability, including whether they can be combined into a breach.

Where the sources line up

So we ran a test. We pointed Evo Continuous Offensive Security (COS) and Claude Security running Mythos at the same application: TaintedPort . It’s a deliberately vulnerable web app that exercises real-world bug classes and a set of registered exploit chains. These are different kinds of tools COS attacks the running application while the two Claude products read source code, and we ran them on the same target to see what each approach proves.

Practical impact for readers

Claude Security on Mythos is a real advance in AI-driven vulnerability discovery. It reasons about source code the way a strong human reviewer does, and it catches classes of flaws that pattern-matching tools miss. But finding a flaw in the code and proving an attacker can exploit these vulnerabilities are different jobs.

Who should pay attention now

Every tool in this test found the server-side request forgery (SSRF) flaw, and that the application's JWT signing secret was hardcoded. Evo COS went further and used the SSRF to reach and retrieve the signing secret from the running application, then used that secret to mint a valid administrator token and take over the admin surface. Two findings, connected into a full account takeover path, were demonstrated against the live app with a runnable proof of concept.

What is still unclear

Above: CHAIN-004 as scored for COS. The two member findings, the SSRF flaw and the hardcoded secret, were reported individually by every tool in this test. Evo COS confirmed that they combine into admin token forgery.

Source notes

Snyk Security Labs