Medium 5.7Published Jul 17, 2026

CVE-2026-15007Denial of service vulnerability in GitHub Enterprise Server allowed service disruption via deeply nested YAML in release notes configuration

Updated under an hour ago (Oct 26, 2026, 9:40 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for GitHub Enterprise Server

Exploited in the last 30 days

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.

CVSS: 5.7 MEDIUM (v4.0, CNA)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
Weakness (CWE): CWE-770
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_P
NVD analysis: Deferred
Record last updated: Jul 17, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

GitHub Enterprise Server github:enterprise_server (from the name)	from 3.17.0 through 3.17.17; fixed at 3.17.18; from 3.18.0 through 3.18.11; fixed at 3.18.12; from 3.19.0 through 3.19.8; fixed at 3.19.9; from 3.20.0 through 3.20.4; fixed at 3.20.5; from 3.21.0 through 3.21.2; fixed at 3.21.3	CNA record

References

References

https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.18	release-notes
https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.12	release-notes
https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.9	release-notes
https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.5	release-notes
https://docs.github.com/en/enterprise-server@3.21/admin/release-notes#3.21.3	release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.