GHSA-cv4x-93xx-wgfj
MEDIUMTekton Pipelines controller panic via long resolver name in TaskRun/PipelineRun
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
github.com/tektoncd/pipeline🐹github.com/tektoncd/pipeline🐹github.com/tektoncd/pipeline🐹github.com/tektoncd/pipeline🐹github.com/tektoncd/pipelineReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A user with permission to create or update a TaskRun or PipelineRun can crash the Tekton Pipelines controller by setting .spec.taskRef.resolver (or .spec.pipelineRef.resolver) to a string of 31 characters or more, causing a denial of service for all reconciliation.
Details
The controller panics in GenerateDeterministicNameFromSpec when building a deterministic ResolutionRequest name. The generated name has the format {resolver}-{hash} and, when the resolver name is long enough, the result exceeds the DNS-1123 label limit of 63 characters.
The truncation logic attempts to find a word boundary using strings.LastIndex(name, " "). Since the generated name never contains spaces (it is composed of the resolver name, a dash, and a hex-encoded hash), LastIndex returns -1, which is then used as a slice bound:
return name[:strings.LastIndex(name[:maxLength], " ")], nil
// strings.LastIndex returns -1 → panic: slice bounds out of range [:-1]
The panic crashes the controller. Because the offending TaskRun or PipelineRun is re-reconciled on restart, the controller enters a CrashLoopBackOff, blocking all TaskRun and PipelineRun reconciliation cluster-wide until the offending resource is manually deleted.
Built-in resolvers use short names (git, cluster, bundles, hub) and are not affected under normal usage. The vulnerability is exploitable by any user who can create TaskRuns or PipelineRuns with a custom resolver name.
Impact
Denial of service — A single malicious TaskRun or PipelineRun with a long resolver name is sufficient to crash the Tekton Pipelines controller into a restart loop, blocking all CI/CD reconciliation cluster-wide until the resource is removed.
Patches
Fixed in versions 1.0.1, 1.3.3, 1.6.1, 1.9.2, 1.10.2.
The fix computes the hash first, then truncates only the prefix (resolver name) to fit within the DNS-1123 label limit, preserving the full hash to maintain determinism and uniqueness of ResolutionRequest names.
Workarounds
Restrict who can create TaskRun and PipelineRun resources via Kubernetes RBAC. There is no validation-side workaround without patching.
Affected Versions
All releases from v0.60.0 through v1.10.0.
The vulnerable truncation logic was introduced in commit ea1fa7ad1fdc ("Remote Resolution Refactor"), first released in v0.60.0 (2024-05-22).
Currently supported affected releases:
- v1.10.x (latest)
- v1.9.x (LTS, EOL 2027-01-30)
- v1.6.x (LTS, EOL 2026-10-31)
- v1.3.x (LTS, EOL 2026-08-04)
- v1.0.x (LTS, EOL 2026-04-29)
Releases prior to v0.60.0 are not affected — the truncation code did not exist.
Acknowledgments
This vulnerability was reported by Oleh Konko (@1seal), who provided a thorough vulnerability analysis, proof-of-concept, and review of the fix. Thank you!
References
- Fix (main): 5eead3f859b9
- Fix (v1.10.x): 01673237c464
- Fix (v1.9.x): edc64bbf2232
- Fix (v1.6.x): 0fa2d66cff81
- Fix (v1.3.x): 5e4905fb6754
- Fix (v1.0.x): ebc197e2b973
- Introduced in:
ea1fa7ad1fdc("Remote Resolution Refactor")
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/tektoncd/pipeline | ≥ 0.60.0&&< 1.0.1 | 1.0.1 |
| 🐹Go | github.com/tektoncd/pipeline | ≥ 1.1.0&&< 1.3.3 | 1.3.3 |
| 🐹Go | github.com/tektoncd/pipeline | ≥ 1.4.0&&< 1.6.1 | 1.6.1 |
| 🐹Go | github.com/tektoncd/pipeline | ≥ 1.7.0&&< 1.9.2 | 1.9.2 |
| 🐹Go | github.com/tektoncd/pipeline | ≥ 1.10.0&&< 1.10.2 | 1.10.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/tektoncd/pipeline. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/tektoncd/pipeline to 1.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-cv4x-93xx-wgfj is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-cv4x-93xx-wgfj is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-cv4x-93xx-wgfj. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-cv4x-93xx-wgfj in your dependencies?
O3 detects GHSA-cv4x-93xx-wgfj across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.