Anthropic’s Opus 5 reportedly cuts browser prompt injection success to zero in 129 tests
The Decoder · rss · 2026-07-25
A The Decoder article reports that Anthropic's Opus 5 may have solved browser-based prompt injection, one of the most persistent security issues for AI agents.
- In 129 test scenarios, Opus 5 combined with Auto Mode achieved a 0% prompt injection success rate for browser agents.
- Without those additional protection layers, the success rate was 3.7%.
- If the result holds up in practice, it would be a major step toward safer browser-operating agents.
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