GHSA-5jp2-vwrj-99rf
MEDIUMTeam scope authorization bypass when Post/Put request with :team_name in body, allows HTTP parameter pollution
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/concourse/concourse🐹github.com/concourse/concourseReal-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
Impact
For some Post/Put Concourse endpoint containing :team_name in the URL, a Concourse user can send a request with body including :team_name=team2 to bypass team scope check to gain access to certain resources belong to any other team. The user only needs a valid user session and belongs to team2.
Exploitable endpoints:
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/jobs/:job_name/builds/:build_name", Method: "POST", Name: RerunJobBuild},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/jobs/:job_name/pause", Method: "PUT", Name: PauseJob},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/jobs/:job_name/unpause", Method: "PUT", Name: UnpauseJob},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/jobs/:job_name/schedule", Method: "PUT", Name: ScheduleJob},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/pause", Method: "PUT", Name: PausePipeline},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/unpause", Method: "PUT", Name: UnpausePipeline},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/expose", Method: "PUT", Name: ExposePipeline},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/hide", Method: "PUT", Name: HidePipeline},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/rename", Method: "PUT", Name: RenamePipeline},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/archive", Method: "PUT", Name: ArchivePipeline},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/resources/:resource_name/versions/:resource_config_version_id/enable", Method: "PUT", Name: EnableResourceVersion},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/resources/:resource_name/versions/:resource_config_version_id/disable", Method: "PUT", Name: DisableResourceVersion},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/resources/:resource_name/versions/:resource_config_version_id/pin", Method: "PUT", Name: PinResourceVersion},
{Path: "/api/v1/teams/:team_name/pipelines/:pipeline_name/resources/:resource_name/unpin", Method: "PUT", Name: UnpinResource},
{Path: "/api/v1/teams/:team_name/artifacts", Method: "POST", Name: CreateArtifact},
Steps to reproduce
- Set up a Concourse deployment with team 1 (with pipeline 1) and team 2. User is in team 2 but not team 1.
- Login as user to team 2.
fly -t ci login -n team2 -u user -p password
- Try pausing pipeline 1 in team 1 using fly. Verify the command output is
pipeline 'pipeline1' not found.
fly -t ci pause-pipeline -p pipeline1
- Send a customized request through
fly curlcommand intend to pause pipeline 1 again.
fly -t ci curl /api/v1/teams/team1/pipelines/pipeline1/pause -- -X PUT -d ":team_name=team2" -H "Content-type: application/x-www-form-urlencoded"
- pipeline 1 in team 1 will be paused.
In step 4, the parameter pollution would allow an user from any team to pause a pipeline that belongs to other team.
Patches
Concourse v6.7.9 and v7.8.3 were both released with a fix on October 12, 2022.
Instead of using FormValue to parse team_name in the request, where allows body parameters to take precedence over URL query string values, both patch versions are now using URL.Query().Get() over multiple scope handlers to prevent the parameter pollution.
Workarounds
No known workarounds for existing versions.
References
- https://github.com/concourse/concourse/pull/8566: PR with the fix
For more information
If you have any questions or comments about this advisory, you may reach us privately at [email protected].
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/concourse/concourse | all versions | 6.7.9 |
| 🐹Go | github.com/concourse/concourse | ≥ 7.0.0&&< 7.8.3 | 7.8.3 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/concourse/concourse. 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/concourse/concourse to 6.7.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5jp2-vwrj-99rf 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-5jp2-vwrj-99rf 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-5jp2-vwrj-99rf. 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-5jp2-vwrj-99rf in your dependencies?
O3 detects GHSA-5jp2-vwrj-99rf across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.