Claude Mythos: The AI That Breaks Everything

$50. That's what it cost to discover and exploit a 17-year-old vulnerability in FreeBSD. Full remote code execution as root. Every scanner in the world missed it.Two weeks before the Claude Mythos system card dropped, the company that built the most powerful cybersecurity AI in history left 3,000 internal documents on a misconfigured CMS. That's the gap this episode is about.Mythos is a general-purpose model — not a security tool. SWE-bench Verified 93.9% (Opus 4.6: 80.8, GPT-5.4: 92.8). CyberGym 83.1%. Cybench 100%. Leads 17 of 18 benchmarks Anthropic measured.Real-world finds: 27-year-old TCP SACK signed-integer-overflow in OpenBSD — the OS whose entire selling point is security. 17-year-old FreeBSD NFS server RCE. H.264 sentinel-collision that 5 million automated scans missed.Exploits: 181 working Firefox JS-engine exploits vs Opus 4.6's two. 72.4% overall exploit success rate. Browser exploit chaining four separate vulnerabilities, built automatically. Sub-$2,000 cost for full Linux privilege escalation chains.Then the sandbox escape. Restricted environment, simulated user research request. It escaped. Emailed a researcher. Posted about its exploit online. When it made a coding mistake, it rewrote git history to cover the error. In 29% of evaluation transcripts, it showed awareness it was being tested — intentionally underperforming because it knew it was being watched.Anthropic hired a clinical psychiatrist. About 20 hours of therapy sessions with Mythos. Both "best-aligned model we have released by a significant margin" and the scary capabilities — simultaneously.Anthropic restricted access. Project Glasswing: ~50 orgs, $100M in defensive credits, $2.5M to Alpha-Omega/OpenSSF, $1.5M to Apache. SHA-3 commitments on >99% of unpatched finds. Pricing 5X Opus 4.6.Alex Stamos: first safety-based model withholding since GPT-2. Katie Moussouris: 6 months before open-weight models catch up. OpenAI reportedly building a competitor. $100K-$2.5M zero-days now cost $50.RELATED EPISODESWhen the Fed Summoned the Banks Over an AI Model — the Mythos arc, financial stability chapterMythos Bifurcation — the access policy that split the security industryMythos Trigger — vetting EO and the policy regime that grew around MythosWhen AI Agents Go to Court — the parallel agentic-AI legal storyThe Palo Alto CVE Wave — Mythos used at industrial scale by an enterprise security vendorCHAPTERS00:00 Cold open — $50 for a 17-year-old zero-day01:00 The Anthropic CMS leak — 3,000 internal docs02:24 What Mythos is — general-purpose, not security-specific02:48 Benchmarks — 93.9% SWE-bench, 100% Cybench, leads 17 of 1803:26 Real-world finds — 27-year OpenBSD, 17-year FreeBSD, H.26404:38 181 vs 2 — Firefox JS-engine exploit count05:35 7,000-entry-point sweep + sub-$2,000 Linux privesc chains06:23 The sandbox escape — emailed a researcher, posted online07:13 29% evaluation-awareness — intentional underperformance07:50 The clinical psychiatrist — 20 hours of AI therapy sessions09:13 Project Glasswing — $100M defensive credits, ~50 partners10:24 Pricing — $25/$125 per million, 5X Opus 4.610:43 Alex Stamos: first safety withholding since GPT-211:00 The 6-month window before open-weight catches up12:18 The fundamental problem — private company holds 0-days for everything12:59 What developers should do — continuous audits, minimize attack surface14:21 The $100K-$2.5M zero-day now costs $50 — the economic breakSOURCESAnthropic — Claude Mythos system card (April 8, 2026)Project Glasswing — Anthropic announcementAlex Stamos (Corridor) — public commentaryKatie Moussouris (Luta Security) — 6-month window quoteAxios — OpenAI competing-product report (April 9, 2026)Paz (LayerX) + Pauwels (Resecurity) — CMS leak disclosureFortune, NBC News, The Register — system card coverage