February 11, 2026

Anthropic published the prompt injection failure rates that enterprise security teams have been asking every vendor for

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JIRAN FAMILY / Unsplash

Run a prompt injection attack against Claude Opus 4.6 in a constrained coding environment, and it fails every time, 0% success rate across 200 attempts, no safeguards needed. Move that same attack to a GUI-based system with extended thinking enabled,...