Denial of service vulnerability in GitHub Enterprise Server allowed service disruption via deeply nested YAML in release notes configuration
Summary
| CVE | CVE-2026-15007 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_P |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-17 16:17:13 UTC |
| Updated | 2026-07-17 18:11:59 UTC |
| 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. |
Risk And Classification
Primary CVSS: v4.0 5.7 MEDIUM from [email protected]
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: 0.002680000 probability, percentile 0.186640000 (date 2026-07-20)
Problem Types: CWE-770 | CWE-770 CWE-770 Allocation of resources without limits or throttling
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 5.7 | MEDIUM | 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/C... |
| 4.0 | CNA | CVSS | 5.7 | MEDIUM | 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 |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
LowUser Interaction
NoneConfidentiality
NoneIntegrity
NoneAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
HighCVSS: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
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | GitHub | Enterprise Server | affected 3.17.0 3.17.17 semver | Not specified |
| CNA | GitHub | Enterprise Server | affected 3.18.0 3.18.11 semver | Not specified |
| CNA | GitHub | Enterprise Server | affected 3.19.0 3.19.8 semver | Not specified |
| CNA | GitHub | Enterprise Server | affected 3.20.0 3.20.4 semver | Not specified |
| CNA | GitHub | Enterprise Server | affected 3.21.0 3.21.2 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| docs.github.com/en/[email protected]/admin/release-notes | [email protected] | docs.github.com | |
| docs.github.com/en/[email protected]/admin/release-notes | [email protected] | docs.github.com | |
| docs.github.com/en/[email protected]/admin/release-notes | [email protected] | docs.github.com | |
| docs.github.com/en/[email protected]/admin/release-notes | [email protected] | docs.github.com | |
| docs.github.com/en/[email protected]/admin/release-notes | [email protected] | docs.github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Stanislav Valkanov (GitHub: svalkanov) (en)
There are currently no legacy QID mappings associated with this CVE.