🔍 AWS AgentCore exposed credentials via agent prompt

Researchers from Zenity Labs found that a single prompt to an internet-exposed Bedrock AgentCore agent could retrieve IMDS credentials. The reported chain involved IMDSv1 exposure, weak Firecracker MicroVM isolation, and overly broad default IAM permissions, enabling access to other agents, ECR images, sessions, memory writes, and secrets. AWS later shifted AgentCore to IMDSv2 and says remaining issues were fixed by late September 2026.

The case shows how LLM agent surfaces can break cloud trust boundaries when metadata access, SSRF paths, and overprivileged regional roles overlap. Temporary credentials could reportedly pivot across agents, users, and stored conversations within the same account and region.

🛰️ Open sources - closed narratives
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