OpenAI: Cross-Model Exploitation via Authentication Bypass and Agentic AI
NCC Group researchers executed a multi-stage attack against OpenAI by exploiting a critical sign-in authentication bypass vulnerability. The attack chain weaponized Anthropic's Claude model as an agentic tool to autonomously develop and refine exploit payloads, facilitating lateral movement from public-facing interfaces to internal development environments. This resulted in unauthorized access to OpenAI's internal codebase, where the researchers submitted a non-malicious pull request as a Proof of Concept (PoC). This incident demonstrates a novel "cross-model" threat vector, where one LLM's capabilities are leveraged to identify and exploit vulnerabilities in a competitor's infrastructure, potentially exposing proprietary model weights, training data, and internal secrets.