{"vulnerability": "cve-2026-50141", "sightings": [{"uuid": "29fadc08-3783-4427-84de-495359ba1b5b", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2026-50141", "type": "seen", "source": "https://gist.github.com/alon710/97fd87eaf3ecb37ec75f6abd3050d94a", "content": "# CVE-2026-50141: CVE-2026-50141: Agent Impersonation via gRPC Metadata Spoofing in Woodpecker CI\n\n> **CVSS Score:** 7.1\n> **Published:** 2026-07-14\n> **Full Report:** https://cvereports.com/reports/CVE-2026-50141\n\n## Summary\nA critical authentication bypass vulnerability in Woodpecker CI allows authenticated agents to impersonate other agents by injecting spoofed agent_id values into gRPC metadata. This flaw is caused by the use of md.Append instead of md.Set on the server-side RPC authorizer.\n\n## TL;DR\nWoodpecker CI server used an unsafe metadata append operation, allowing authenticated agents to spoof their identity and impersonate any other registered agent.\n\n## Exploit Status: POC\n\n## Technical Details\n\n- **CWE ID**: CWE-290, CWE-639\n- **Attack Vector**: Network\n- **CVSS v4.0 Score**: 7.1 (High)\n- **Exploit Status**: PoC (Proof of Concept)\n- **Affected Component**: gRPC Authorization Interceptor (server/rpc/authorizer.go)\n- **Fixed Version**: v3.14.1\n\n## Affected Systems\n\n- Woodpecker CI Server\n- **Woodpecker CI**: >= 3.0.0, < 3.14.1 (Fixed in: `3.14.1`)\n\n## Mitigation\n\n- Upgrade to Woodpecker CI server and agent version 3.14.1 or higher.\n- Disable user or organization-level agent registration to restrict authorized access to trusted administrators.\n\n**Remediation Steps:**\n1. Set the environment variable WOODPECKER_DISABLE_USER_AGENT_REGISTRATION=true on the Woodpecker server.\n2. Audit existing agents and remove any unauthorized or user-registered agents from the database.\n3. Deploy the updated Woodpecker server container image using version 3.14.1 or later.\n\n## References\n\n- [GitHub Security Advisory](https://github.com/woodpecker-ci/woodpecker/security/advisories/GHSA-g7mm-9vx7-jm7h)\n- [Woodpecker Security Issue 21](https://github.com/woodpecker-ci/woodpecker-security/issues/21)\n- [Woodpecker Issue 6541](https://github.com/woodpecker-ci/woodpecker/issues/6541)\n- [Pull Request 6567](https://github.com/woodpecker-ci/woodpecker/pull/6567)\n- [Pull Request 6569](https://github.com/woodpecker-ci/woodpecker/pull/6569)\n- [NVD CVE-2026-50141 Detail](https://nvd.nist.gov/vuln/detail/CVE-2026-50141)\n- [CVE-2026-50141 Record](https://www.cve.org/CVERecord?id=CVE-2026-50141)\n\n\n---\n*Generated by [CVEReports](https://cvereports.com/reports/CVE-2026-50141) - Automated Vulnerability Intelligence*", "creation_timestamp": "2026-07-14T19:11:47.294997Z"}]}