GitHub Enterprise Server: path traversal
High8.6CVE-2026-15343 · Published Jul 17, 2026
A path traversal vulnerability was identified in GitHub Enterprise Server that allowed an attacker who had code execution inside the Dependabot updater container to write files to arbitrary repository paths, including GitHub Actions workflow files under .github/workflows/ as the path validation did not check the effective path which the attacker could control through the dependency file's directory and symlink target. If the repository used a pull_request_target workflow or had auto-merge enabled, an injected workflow could execute with access to the repository's GitHub Actions secrets. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.21.3, 3.20.5, 3.19.9, 3.18.12, 3.17.18.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Enterprise Server Product | >= 3.17.0, <= 3.17.17 | No fix yet |
| >= 3.18.0, <= 3.18.11 | No fix yet | |
| >= 3.19.0, <= 3.19.8 | No fix yet | |
| >= 3.20.0, <= 3.20.4 | No fix yet |
Details and references
- CVSS 4.0
- CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-22
- www.cve.org/CVERecord?id=CVE-2026-15343
- nvd.nist.gov/vuln/detail/CVE-2026-15343
- docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.18
- docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.12
- docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.9
- docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.5
- docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.3
More GitHub advisories
All GitHub| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Aug 6 | Safe-outputs config emitter: JSON injection via templated values despite env-var indirection | High8.5 | v0.78.0 |
| Aug 5 | GitHub Enterprise Server: denial of service | Medium6.6 | No fix yet |
| Aug 5 | GitHub Enterprise Server: path traversal | High8.8 | No fix yet |
| Jul 17 | GitHub Enterprise Server: missing authorization | Medium5.3 | No fix yet |
| Jul 17 | GitHub Enterprise Server: denial of service | Medium5.7 | No fix yet |
| Jul 1 | GitHub Enterprise Server: improper authorization | Medium5.3 | No fix yet |