nnU-Net is a semantic segmentation framework that automatically adapts its pipeline to a dataset. Prior to 2.4.1, the nnU-Net Issue Triage workflow in .github/workflows/issue-triage.yml is vulnerable to Agentic Workflow Injection. The workflow sets allowed_non_write_users: ${{ github.event.issue.user.login }}, which means any logged-in GitHub user who opens an issue can reach this agentic workflow with attacker-controlled content. Untrusted issue title and body content are embedded directly into the prompt of anthropics/claude-code-action, and the workflow then runs a command-capable Claude agent with permission to comment on and relabel the current issue via gh. Because this workflow is triggered automatically on issues.opened, an external attacker can submit a crafted issue that steers the agent beyond its intended issue-triage purpose and influences authenticated issue actions. This vulnerability is fixed in 2.4.1.
Fix
Public exploits 2
- pvharmo2/gha-lab-733c168b88 PoC on GitHub
- sushant-me/agentic-workflow-injection PoC on GitHub
Each line links to the index that lists it, never to exploit code. Exploit-DB's "verified" and a Metasploit rank of good or better count as verified; a PoC-in-GitHub entry is a repository's claim.
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/MIC-DKFZ/nnUNet/security/advisories/GHSA-63mx-j37w-gh59 Exploit, Mitigation, Vendor Advisory
- https://github.com/MIC-DKFZ/nnUNet/security/advisories/GHSA-63mx-j37w-gh59 Exploit, Mitigation, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 7.2 · dkfzNVD modified 2026-10-26 18:10
Affected (CPE criteria) 1
cpe:2.3:a:dkfz:nnu-net:*:*:*:*:*:*:*:*
References 2
- https://github.com/MIC-DKFZ/nnUNet/security/advisories/GHSA-63mx-j37w-gh59 Exploit, Mitigation, Vendor Advisory
- https://github.com/MIC-DKFZ/nnUNet/security/advisories/GHSA-63mx-j37w-gh59 Exploit, Mitigation, Vendor Advisory