CVE-2026-40938 Tekton Pipelines: Git Resolver Unsanitized Revision Parameter Enables git Argument Injection Leading to RCE

What is CVE-2026-40938?

CVE-2026-40938 is a high-severity command injection vulnerability in tektoncd pipeline, published on 21 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

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, the git resolver's revision parameter is passed directly as a positional argument to git fetch without any validation that it does not begin with a - character. Because git parses flags from mixed positional arguments, an attacker can inject arbitrary git fetch flags such as --upload-pack=<binary>. Combined with the validateRepoURL function explicitly permitting URLs that begin with / (local filesystem paths), a tenant who can submit ResolutionRequest objects can chain these two behaviors to execute an arbitrary binary on the resolver pod. The tekton-pipelines-resolvers ServiceAccount holds cluster-wide get/list/watch on all Secrets, so code execution on the resolver pod enables full cluster-wide secret exfiltration. Versions 1.0.2, 1.3.4, 1.6.2, 1.9.3, and 1.11.1 fix the issue.

Weakness: CWE-88

Which versions are affected by CVE-2026-40938?

11 open source packages ship an affected version, including github.com/tektoncd/pipeline. It affects 1 product.

Products include Linuxfoundation Tekton Pipelines.

How do I fix CVE-2026-40938?

Upgrade github.com/tektoncd/pipeline to a fixed version for your release line: 1.0.2, 1.3.4, 1.6.2 or 1.9.3.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2026-40938 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40938 exists.

Other vulnerabilities in tektoncd pipeline

• CVE-2026-33211 Tekton Pipelines git resolver has path traversal that allows reading arbitrary files from the resolver pod Critical 9.6
• CVE-2026-40161 Tekton Pipelines: Git resolver API mode leaks system-configured API token to user-controlled serverURL High 7.7
• CVE-2026-25542 Tekton Pipelines: VerificationPolicy regex pattern bypass via substring matching Medium 6.5
• CVE-2026-40924 Tekton Pipelines: HTTP Resolver Unbounded Response Body Read Enables Denial of Service via Memory Exhaustion Medium 6.5
• CVE-2026-33022 Tekton Pipelines: Controller can panic when setting long resolver names in TaskRun/PipelineRun Medium 6.5

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as CLEANSTART-2026-KA98572, GHSA-94jr-7pqp-xhcq, GO-2026-5272.