OpenAI launches GPT-5.5-Cyber, a dedicated model for cybersecurity.

OpenAI has announced a limited preview of GPT-5.5-Cyber, initially made available to vetted cyber defenders. Based on the Trusted Access for Cyber (TAC) framework, the model reduces the rejection rate for security-related tasks compared to GPT-5.5, supports defense workflows such as vulnerability verification and malware analysis, while retaining protection against malicious activity.