OpenAI releases GPT-5.5-Cyber complete version, CyberGym benchmark surpasses Mythos 5

Odaily Planet Daily reported that OpenAI has announced an upgrade to the Daybreak network defense toolchain and officially launched the complete version of the GPT-5.5-Cyber model, designed for cybersecurity defense scenarios.

In the CyberGym benchmark test, which evaluates the ability of AI agents to reproduce known vulnerabilities, GPT-5.5-Cyber achieved a single-model score of 85.6%, surpassing GPT-5.5's 81.8% and Anthropic Mythos 5's 83.8%.

OpenAI stated that as AI significantly improves the efficiency of vulnerability discovery, the core bottleneck in the cybersecurity field is shifting from "finding vulnerabilities" to "automatically fixing vulnerabilities." To this end, the company has simultaneously upgraded the Codex Security plugin, allowing developers to automatically analyze vulnerabilities and generate fix patches within the Codex environment. Since the preview release in March this year, Codex Security has scanned over 30 million code commits and automatically confirmed fixes for 500,000 security defects. The new version also supports CodeQL query integration and SARIF standard file export.

Additionally, in collaboration with organizations such as Trail of Bits and HackerOne, OpenAI has launched the "Patch the Planet" open-source security project, providing ChatGPT Pro subscriptions and API credits to over 30 major open-source projects, including cURL and Go, with a team of security experts manually verifying patch quality. Regarding the Daybreak partner program, security vendors like Palo Alto Networks and Wiz have already been among the first to integrate the relevant capabilities.