Tekton Pipelines: VolumeMount path restriction bypass via missing filepath.Clean in /tekton/ check

Summary

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.

Timeline

1. Apr 21, 2026, 8:50 PM UTCCVE published
2. Apr 22, 2026, 1:50 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. May 22, 2026, 3:41 PM UTCRecord last updated

Affected versions

• tektoncd pipeline

  From 1.0.0 · fixed in 1.0.2; From 1.2.0 · fixed in 1.3.4; From 1.4.0 · fixed in 1.6.2; From 1.7.0 · fixed in 1.9.3; From 1.10.0 · fixed in 1.11.1

• github.com/tektoncd/pipelineGo

  From 1.0.0 · fixed in 1.0.2; From 1.1.0 · fixed in 1.3.4; From 1.4.0 · fixed in 1.6.2; From 1.7.0 · fixed in 1.9.3; From 1.10.0 · fixed in 1.11.1

• github.com/tektoncd/pipelineGo

  From 1.10.0 · fixed in 1.11.1

• github.com/tektoncd/pipelineGo

  From 1.7.0 · fixed in 1.9.3

• github.com/tektoncd/pipelineGo

  From 1.4.0 · fixed in 1.6.2

• github.com/tektoncd/pipelineGo

  From 1.2.0 · fixed in 1.3.4

• github.com/tektoncd/pipelineGo

  From 1.0.0 · fixed in 1.0.2

References 2