CVE-2026-40923: linuxfoundation tekton_pipelines Path Traversal

Vulnerability summary

CVE-2026-40923 is a medium (CVSS 5.4) Path Traversal vulnerability in linuxfoundation tekton_pipelines. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 23.3% of scored vulnerabilities.

Timeline

1. 21-04-2026
   PublishedVulnerability first disclosed.
2. 22-05-2026
   Last modifiedVulnerability information updated.

Description

Tekton Pipelines project provides k8s-style resources for declaring CI/CD-style pipelines. Starting in version 1.0.0 and prior to versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1, a validation bypass in the VolumeMount path restriction allows mounting volumes under restricted /tekton/ internal paths by using .. path traversal components. The restriction check uses strings.HasPrefix without filepath.Clean, so a path like /tekton/home/../results passes validation but resolves to /tekton/results at runtime. Versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1 fix the issue.

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.