CVE-2026-8606 (GCVE-0-2026-8606)

Vulnerability from cvelistv5 – Published: 2026-05-26 23:59 – Updated: 2026-05-26 23:59
VLAI
Title
Server-Side Request Forgery in GitHub Enterprise Server via Advisory Package URL Endpoint
Summary
A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an attacker to cause the server to issue HTTP requests to internal services via the security advisories package lookup feature. By directing requests to an internal management service and measuring response timing, an attacker could infer the values of sensitive environment variables, including signing secrets and private keys. Exploitation required GitHub Packages to be enabled; on instances not running in private mode the vulnerability was exploitable without authentication, otherwise any authenticated user could exploit it. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21.1 and was fixed in versions 3.20.3, 3.19.7, 3.18.10, 3.17.16, and 3.16.19. This vulnerability was reported via the GitHub Bug Bounty program.
Severity
7 (High)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:H/SI:H/SA:N
CWE
  • CWE-918 - Server-Side request forgery (SSRF)
Assigner
References
Impacted products
Vendor Product Version
GitHub Enterprise Server Affected: 3.21.0 , < 3.21.1 (semver)
Affected: 3.20.0 , ≤ 3.20.2 (semver)
Affected: 3.19.0 , ≤ 3.19.6 (semver)
Affected: 3.18.0 , ≤ 3.18.9 (semver)
Affected: 3.17.0 , ≤ 3.17.15 (semver)
Affected: 3.16.0 , ≤ 3.16.18 (semver)
Create a notification for this product.
Credits
R31n
Show details on NVD website
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          "url": "https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.19"
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      "source": {
        "discovery": "UNKNOWN"
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}


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Taxonomy of the tags.




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

Author Source Type Date Other

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.