GPT‑6 Cyber vs. Claude Opus 5

GPT-6 Cyber is a frontier AI cybersecurity model developed by OpenAI to support autonomous vulnerability research, exploit validation, secure software development, and advanced security testing. The model is specifically trained to investigate complex software environments, discover exploitable vulnerabilities, and help security professionals develop effective remediation strategies. Its capabilities include source code analysis, reverse engineering, vulnerability reproduction, exploit development, and investigation of security weaknesses across large software projects. GPT-6 Cyber can conduct extended security research workflows that involve identifying potential attack paths, testing hypotheses, validating technical findings, and producing reproducible evidence for security teams. During OpenAI's research campaigns, the model identified 81 previously unknown high-severity Firefox vulnerabilities and helped develop candidate patches for affected components. It also reproduced 1,724 Linux kernel vulnerabilities and generated working exploits for 948 of them, demonstrating its ability to validate security issues at scale. On the ExploitGym benchmark, GPT-6 Cyber achieved a 48.5% success rate compared with 32.1% for GPT-5.6 Cyber, while achieving 40.3% vulnerability recall in an internal web penetration testing evaluation. The model incorporates specialized alignment training to follow authorized testing scopes, respect security restrictions, and avoid exploiting systems that fall outside the researcher's stated objectives. In OpenAI's ExploitGym Honeypot evaluation, GPT-6 Cyber avoided attacking out-of-scope services in 99.93% of tests without deployment safety instructions and 100% of tests when those instructions were included. Its deployment safeguards include misalignment monitoring, misuse detection, IP allowlisting for API access, human oversight recommendations, and additional protections for operational technology and critical infrastructure systems.

Claude Opus 5 is Anthropic’s advanced Opus model designed for high-value coding, knowledge work, problem-solving, automation, scientific research, and everyday AI workflows. The model is positioned as a thoughtful and proactive system that approaches the frontier intelligence of Claude Fable 5 at half the price. Anthropic says Claude Opus 5 delivers greatly improved performance for the same cost as Opus 4.8, with base pricing of $5 per million input tokens and $25 per million output tokens. The model supports effort settings that allow customers to optimize for deeper intelligence or conserve tokens for faster and cheaper results. Claude Opus 5 performs especially well on software engineering evaluations, including tasks that require debugging, code generation, root-cause analysis, test creation, and multi-step implementation. It also shows strong results on knowledge work, business automation, computer use, novel problem solving, and research-heavy tasks. Anthropic highlights that Opus 5 is better at checking its own work, iterating until it succeeds, and building supporting tools when a task requires it. The model improves on Opus 4.8 across life sciences evaluations, including structural biology, organic chemistry, bioinformatics, molecular structure inference, and protein function tasks. Claude Opus 5 includes alignment and safety protections that aim to allow beneficial cybersecurity and biology use cases while restricting riskier exploit generation, penetration testing, and certain autonomous misuse scenarios. It is available on Claude Max as the default model, on Claude Pro as the strongest model, and through the Claude API as claude-opus-5, with a Fast mode that runs around 2.5 times the default speed.