CVE-2026-40938

This Important flaw in Tekton Pipelines allows an authenticated user to achieve arbitrary code execution on the resolver pod by injecting malicious commands into the git resolver's revision parameter. This vulnerability happens because the revision parameter is passed as a positional argument to the git fetch command without any previous validation whether the parameter's value doesn't start with - character. Combining this lack of validation with the fact the function which validates the repository URL explicitly allows a repository URL to being with /, translating to a local filesystem. An attacker with enough privileges to perform an operation which trigger resolvers to use the ResolutionRequest function can chain both behaviors to trick Tekton Pipelines to load and execute an arbitrary binary on the resolver pod.

Exploring this vulnerability may be considered of a high complexity as an attacker needs to either know an existing valid git repository located at a predicable path already in the resolver pod or a default URL configuration pointing to a local filesystem's path.

A successful exploitation of the flaw can lead to the exfiltration of all cluster-wide secrets, posing a significant risk to the integrity and confidentiality of the OpenShift environment. Additionally, depending on the data included in the kubeconfig files, an attacker may achieve privilege escalation or perform lateral movements within the targeted cluster.