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.
Exploitability
AV:NAC:LPR:LUI:NScope
S:UImpact
C:NI:HA:N6.5/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NOther