ChainThink reports that on July 25, according to the Anthropic Opus 5 system card, the company stated that Opus 5 is its most resilient model to date against prompt injection attacks.
The system card shows that, based on the prompted evaluation and red team test results, Opus 5 demonstrates stronger resistance to malicious prompt injection.
Prompt injection is one of the core risks in AI security, where attackers can craft inputs to bypass model safety restrictions and induce unintended behavior. Anthropic has disclosed related evaluation details on page 73 of the System Card.
