CVE-2026-15783 (GCVE-0-2026-15783)

Vulnerability from cvelistv5 – Published: 2026-07-17 15:20 – Updated: 2026-07-17 16:55
VLAI
Title
Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed reading private repository metadata via delegated bypass rule suites
Summary
A missing authorization vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user with write access to any repository to read metadata from private repositories they did not have access to, including private repository owners and names, branch names, commit SHAs, commit messages, and the pushing actor. The delegated bypass endpoint resolved a rule suite directly from an attacker-supplied, encoded identifier without verifying that the requesting user could read the rule suite's repository, and because these identifiers are sequential an attacker could enumerate them across the instance. 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
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
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
Ahmed Mamdoh (0hmz)
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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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.