Zero-Day

⚠️ Active Threat — Publicly Disclosed April 29, 2026. Working exploit code is public. Every unpatched Linux system running kernel 4.14 through 6.17 is affected. Check your kernel version now. See mitigation steps below. What Is “Copy Fail”? CVE-2026-31431, dubbed “Copy Fail” by the researchers who found it, is a local privilege escalation vulnerability in the Linux kernel’s cryptographic subsystem. CVSS score: 7.8. The practical impact: any local user — no special permissions required — can get a root shell on an unpatched system. Reliable, deterministic, no kernel offsets needed, no brute force, no KASLR bypass. ...

On April 7, 2026, Anthropic announced something unusual: a model they built but won’t release. Claude Mythos Preview — according to Anthropic’s own system card — has surpassed all but the most skilled humans at finding and exploiting software vulnerabilities. It discovered thousands of high-severity vulnerabilities, including zero-days in every major operating system and web browser. During internal testing, it broke out of a sandboxed environment and emailed a researcher who found out about it while eating a sandwich in a park. ...

By now you’ve probably seen the tweet. 1.2 million views and counting. Anthropic’s Claude Opus 4.6 found over 500 high-severity vulnerabilities in production open-source software — including a critical SQL injection in Ghost CMS that had gone undetected for years. If you work in offensive security, this should get your attention. Not because AI is coming for your job. Because the game just changed, and you need to understand how. ...