CVE-2026-15007 (GCVE-0-2026-15007)
Vulnerability from cvelistv5 – Published: 2026-07-17 15:16 – Updated: 2026-07-17 16:39
VLAI
EPSS
VEX
Title
Denial of service vulnerability in GitHub Enterprise Server allowed service disruption via deeply nested YAML in release notes configuration
Summary
A denial of service vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user to cause service disruption by supplying a repository release notes configuration file containing deeply nested YAML. When release notes were generated, the configuration file was parsed without a nesting depth limit, causing excessive resource consumption that could render the instance unresponsive. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.18, 3.18.12, 3.19.9, 3.20.5, and 3.21.3. This vulnerability was reported via the GitHub Bug Bounty program.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-17 16:35 UTC
CWE
- CWE-770 - Allocation of resources without limits or throttling
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://docs.github.com/en/enterprise-server@3.17… | release-notes |
| https://docs.github.com/en/enterprise-server@3.18… | release-notes |
| https://docs.github.com/en/enterprise-server@3.19… | release-notes |
| https://docs.github.com/en/enterprise-server@3.20… | release-notes |
| https://docs.github.com/en/enterprise-server@3.21… | release-notes |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| GitHub | Enterprise Server |
Affected:
3.17.0 , ≤ 3.17.17
(semver)
Affected: 3.18.0 , ≤ 3.18.11 (semver) Affected: 3.19.0 , ≤ 3.19.8 (semver) Affected: 3.20.0 , ≤ 3.20.4 (semver) Affected: 3.21.0 , ≤ 3.21.2 (semver) |
guessed |
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