CVE-2026-15007 (GCVE-0-2026-15007)

Vulnerability from cvelistv5 – Published: 2026-07-17 15:16 – Updated: 2026-07-17 16:39
VLAI
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
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-770 - Allocation of resources without limits or throttling
Assigner
References
Impacted products
Vendor Product Version
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)
Create a notification for this product.
Credits
Stanislav Valkanov (GitHub: svalkanov)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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