Incorrect Regular Expression Affecting tkn package, versions <0.44.1-r4
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-CHAINGUARDLATEST-TKN-16535602
- published8 May 2026
- disclosed21 Apr 2026
Introduced: 21 Apr 2026
CVE-2026-25542 (opens in a new tab)How to fix?
Upgrade Chainguard tkn to version 0.44.1-r4 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream tkn package and not the tkn package as distributed by Chainguard.
See How to fix? for Chainguard relevant fixed versions and status.
Tekton Pipelines project provides k8s-style resources for declaring CI/CD-style pipelines. From 0.43.0 to 1.11.0, 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.