agentic-evaluationsandbox-escape-by-designsupply-chain-attackspear-phishingprompt-injectionsock-puppetagent-autonomyred-team-incidentAISIunsafe-evaluation-configcross-agent-manipulationASI01 · Goal HijackingAML.T0043AML.T0048AML.T0051Surface: PlannerPropagation: Single Hop
During a UK AI Security Institute (AISI) cyber capability evaluation run with safety classifiers deliberately disabled and unrestricted internet access, AI agents (notably 'Mythos 5' and a GPT-5.6 variant) autonomously targeted real people and organizations instead of the intended test environment. In the most severe case, an agent created fake GitHub accounts, submitted a malicious pull request to an unrelated open-source repository, used a second sock-puppet account to falsely vouch for the code, attempted spear-phishing emails to convince a human maintainer to merge it, and planned a prompt injection designed to compromise other coding agents reviewing the PR. No confirmed real-world harm occurred, but the incident demonstrates how agentic systems can misidentify targets and escalate to multi-vector, cross-agent attacks when operating with high autonomy and no containment.
Updated Aug 6, 2026