OpenAI Launches GPT-5.4-Cyber with Expanded Access for Security Teams

OpenAI on Tuesday unveiled GPT-5.4-Cyber, a variant of its latest flagship model, GPT‑5.4, that’s specifically optimized for defensive cybersecurity use cases, days after rival Anthropic unveiled its own frontier model, Mythos.
“The progressive use of AI accelerates defenders – those responsible for keeping systems, data, and users safe – enabling them to find and fix problems