Anthropic tackles prompt injections for Claude's browser agent
Anthropic just rolled out new defenses against prompt injection attacks, helping Claude Opus 4.5 resist malicious instructions hidden across the web. The upgrades combine reinforcement learning with improved classifiers to drive attack success rates down to 1%, allowing the Claude for Chrome extension to expand into beta for Max plan subscribers. Why it matters: as agents take over real-world browsing and form filling, securing untrusted web content is critical—though Anthropic stresses a 1% risk is far from a solved problem.