Brotli decoder memory corruption flaw exposes Node.js, Bun, Python, and many other programs to code execution

OpenAI's Codex Security team reported CVE-2026-111497, a memory corruption flaw in Google's Brotli decoder that Google rates 9.2, where crafted compressed data overwrites past a buffer and can crash, leak memory, or run attacker code. Because the vulnerable C code is bundled widely, every program shipping it inherits the bug, including Node.js, Bun, .NET, Envoy, Istio, Python Brotli bindings, the Ruby gem, and others, with FFmpeg, ClickHouse, and Apache Arrow also affected. Each project needs its own update, such as Node.js 24.22.1 or Bun 1.4.4. Imperva demonstrated code execution on Node.js 24, calling it Node2Shell, but no in-the-wild exploitation is reported.

Check

Inventory software that decodes Brotli, including Node.js, Bun, .NET, Envoy, Istio, and Python bindings, and apply each project's fixed version.

Affected

Programs bundling the vulnerable Brotli decoder can be crashed or driven to code execution by crafted compressed data, regardless of the application's own code.

Fix

Update every affected runtime and library to its patched release, prioritize internet-facing services that accept Brotli-compressed input, and track fixes for FFmpeg and others still pending.