After Sam Altman criticized Anthropic for restricting its cybersecurity tool Mythos to select users, he confirmed OpenAI would adopt a similar approach with its tool, Cyber.
Altman announced in a post on X that OpenAI will start rolling out GPT-5.5 Cyber “to critical cyber defenders” soon. OpenAI offers an application on its website for individuals to submit their credentials and intended use to gain access.
Cyber can perform tasks like penetration testing, vulnerability identification (and exploitation), and malware reverse engineering. It’s designed to help companies identify security vulnerabilities and test defenses, with concerns about potential misuse by malicious actors.
When Anthropic limited access to Mythos, Altman labeled it as fear-based marketing. Critics agreed, suggesting Anthropic’s rhetoric was exaggerated. However, an unauthorized group allegedly accessed Mythos nonetheless.
OpenAI is aiming to make Cyber more widely accessible by working with the U.S. government and identifying additional users with verified cybersecurity credentials.