CVE-2026-15007Denial of service vulnerability in GitHub Enterprise Server allowed service disruption via deeply nested YAML in release notes configuration
- 5.7MediumCVSS base score
- 0.64%Exploitation in 30 daysEPSS · top 49% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By GitHub_P
- 10 days later
· 10 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_PCNA (assigner) | 4.0 | Medium5.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:U |
| NVDNVD · Deferred | 4.0 | Medium5.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:U/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 |
- EPSS (exploitation in 30 days)
- 0.64% · top 49% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.7.
Affected products
- affected 3.17.0 – ≤ 3.17.17
- affected 3.18.0 – ≤ 3.18.11
- affected 3.19.0 – ≤ 3.19.8
- affected 3.20.0 – ≤ 3.20.4
- affected 3.21.0 – ≤ 3.21.2
References
References5
- https://docs.github.com/en/[email protected]/admin/release-notes#3.17.18 (opens in a new tab)release-notes
- https://docs.github.com/en/[email protected]/admin/release-notes#3.18.12 (opens in a new tab)release-notes
- https://docs.github.com/en/[email protected]/admin/release-notes#3.19.9 (opens in a new tab)release-notes
- https://docs.github.com/en/[email protected]/admin/release-notes#3.20.5 (opens in a new tab)release-notes
- https://docs.github.com/en/[email protected]/admin/release-notes#3.21.3 (opens in a new tab)release-notes
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-45188 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-15007)Record last updated .