A path traversal vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to delete arbitrary files and directories on the instance, including the entire user storage directory containing Git LFS objects, release assets, attachments, and avatars. The X-GitHub-Request-Id request header was used without sanitization as a filesystem path segment for the upload buffer directory, so a traversal value pointed the buffer at an arbitrary path and the deferred cleanup routine recursively removed the traversed target. Exploitation required only network reachability to the instance and no authentication, and it worked even when private mode was enabled. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.21.4, 3.20.6, 3.19.10, 3.18.13 and 3.17.19. This vulnerability was reported via the GitHub Bug Bounty program.
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History
Wed, 05 Aug 2026 21:45:00 +0000
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Github
Github enterprise Server |
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Github
Github enterprise Server |
Wed, 05 Aug 2026 20:15:00 +0000
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| Description | A path traversal vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to delete arbitrary files and directories on the instance, including the entire user storage directory containing Git LFS objects, release assets, attachments, and avatars. The X-GitHub-Request-Id request header was used without sanitization as a filesystem path segment for the upload buffer directory, so a traversal value pointed the buffer at an arbitrary path and the deferred cleanup routine recursively removed the traversed target. Exploitation required only network reachability to the instance and no authentication, and it worked even when private mode was enabled. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.21.4, 3.20.6, 3.19.10, 3.18.13 and 3.17.19. This vulnerability was reported via the GitHub Bug Bounty program. | |
| Title | Path traversal in GitHub Enterprise Server allowed unauthenticated deletion of instance storage via the X-GitHub-Request-Id header | |
| Weaknesses | CWE-22 | |
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| Metrics |
cvssV4_0
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Status: PUBLISHED
Assigner: GitHub_P
Published:
Updated: 2026-08-05T20:05:53.800Z
Reserved: 2026-07-27T13:19:24.539Z
Link: CVE-2026-17556
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OpenCVE Enrichment
Updated: 2026-08-05T21:30:16Z
Weaknesses