nnU-Net: Agentic workflow injection in `.github/workflows/issue-triage.yml` of `MIC-DKFZ/nnUNet`_CVE-2026-44246

7.2 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Description

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.

Basic Information

ID CVE-2026-44246

Source GitHub_M

Published May 12, 2026 at 20:41

Affected Product

Vendor MIC-DKFZ

Product nnUNet

Version < 2.4.1

Affected Versions MIC-DKFZ nnUNet < 2.4.1

CWE Classification

CWE-1427

References

github.com /MIC-DKFZ/nnUNet/security/advisories/GHSA-63mx-j37w-gh59

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    "published": "2026-05-12T20:41:32.162Z",
    "modified": "2026-05-12T20:41:32.162Z",
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