CVE-2026-8606

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.

Affected Software

VendorProductVersion RangeStatus
GitHubEnterprise Server3.21.0 < 3.21.1affected
GitHubEnterprise Server3.20.0 <= 3.20.2affected
GitHubEnterprise Server3.19.0 <= 3.19.6affected
GitHubEnterprise Server3.18.0 <= 3.18.9affected
GitHubEnterprise Server3.17.0 <= 3.17.15affected
GitHubEnterprise Server3.16.0 <= 3.16.18affected

Weaknesses

  • CWE-918: CWE-918 Server-Side request forgery (SSRF)

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References