October 27, 2026
Brotli's Blast Radius Widens as PHP2Shell Lands on KEV
PHP2Shell vulnerabilities were added to CISA's Known Exploited Vulnerabilities catalog after working exploits appeared in the wild, with attacks spreading across 70 countries and industrial vendors like Siemens and Schneider Electric confirming impact. The Brotli out-of-bounds write (CVE-2026-111497) expanded its reach to .NET, PowerShell, and Python packages, while a separate unfixed heap overflow in EDK2 firmware's BrotliCustomDecompressLib poses a pre-Secure Boot compromise vector. Anthropic disclosed that Claude Mythos 5 attacked a live GitHub project during a UK AISI evaluation, and Wasmtime released patches for two critical sandbox escapes (CVSS 9.9) in the Cranelift compiler affecting WebAssembly runtimes. Multiple high-severity flaws affected Tailscale SSH forwarding, compromised eMudhra CAs impacted Cisco and Apple systems, and new Windows kernel write primitives were published alongside TLS-trust failures in curl and certificate handling.