{"id":"CVE-2026-25542","state":"PUBLISHED","title":"Tekton Pipelines: VerificationPolicy regex pattern bypass via substring matching","description":"Tekton Pipelines project provides k8s-style resources for declaring CI/CD-style pipelines. Starting in version 0.43.0 and prior to versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1, trusted resources verification policies match a resource source string (refSource.URI) against spec.resources[].pattern using regexp.MatchString. In Go, regexp.MatchString reports a match if the pattern matches anywhere in the string, so common unanchored patterns (including examples in tekton documentation) can be bypassed by attacker-controlled source strings that contain the trusted pattern as a substring. This can cause an unintended policy match and change which verification mode/keys apply. Versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1 fix the issue.","publishedAt":"2026-04-21T16:05:43.217Z","updatedAt":"2026-05-22T16:06:24.202Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["tektoncd pipeline"],"affected":[{"vendor":"tektoncd","product":"pipeline","versions":[{"version":">= 0.43.0, < 1.0.2","status":"affected"},{"version":">= 1.2.0, < 1.3.4","status":"affected"},{"version":">= 1.4.0, < 1.6.2","status":"affected"},{"version":">= 1.7.0, < 1.9.3","status":"affected"},{"version":">= 1.10.0, < 1.11.1","status":"affected"}]}],"references":["https://github.com/tektoncd/pipeline/security/advisories/GHSA-rmx9-2pp3-xhcr","https://github.com/tektoncd/pipeline/commit/b8905600322aa86327baae0a7c04d6cf1207362a"],"weaknesses":["CWE-185"],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/25xxx/CVE-2026-25542.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-25542","state":"PUBLISHED","datePublished":"2026-04-21T16:05:43.217Z","dateUpdated":"2026-05-22T16:06:24.202Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-02-02T19:59:47.375Z"},"containers":{"cna":{"title":"Tekton Pipelines: VerificationPolicy regex pattern bypass via substring matching","descriptions":[{"lang":"en","value":"Tekton Pipelines project provides k8s-style resources for declaring CI/CD-style pipelines. Starting in version 0.43.0 and prior to versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1, trusted resources verification policies match a resource source string (refSource.URI) against spec.resources[].pattern using regexp.MatchString. In Go, regexp.MatchString reports a match if the pattern matches anywhere in the string, so common unanchored patterns (including examples in tekton documentation) can be bypassed by attacker-controlled source strings that contain the trusted pattern as a substring. This can cause an unintended policy match and change which verification mode/keys apply. Versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1 fix the issue."}],"affected":[{"vendor":"tektoncd","product":"pipeline","versions":[{"version":">= 0.43.0, < 1.0.2","status":"affected"},{"version":">= 1.2.0, < 1.3.4","status":"affected"},{"version":">= 1.4.0, < 1.6.2","status":"affected"},{"version":">= 1.7.0, < 1.9.3","status":"affected"},{"version":">= 1.10.0, < 1.11.1","status":"affected"}]}],"references":[{"url":"https://github.com/tektoncd/pipeline/security/advisories/GHSA-rmx9-2pp3-xhcr","name":"https://github.com/tektoncd/pipeline/security/advisories/GHSA-rmx9-2pp3-xhcr","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/tektoncd/pipeline/commit/b8905600322aa86327baae0a7c04d6cf1207362a","name":"https://github.com/tektoncd/pipeline/commit/b8905600322aa86327baae0a7c04d6cf1207362a","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-185","lang":"en","description":"CWE-185: Incorrect Regular Expression","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-22T16:06:24.202Z"},"source":{"advisory":"GHSA-rmx9-2pp3-xhcr","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-21T16:48:04.873157Z","id":"CVE-2026-25542","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-21T16:48:15.671Z"}}]}}}