CVE-2026-1355 (GCVE-0-2026-1355)

Vulnerability from cvelistv5 – Published: 2026-02-18 20:42 – Updated: 2026-02-18 20:42
VLAI?
Title
Missing Authorization Check in GitHub Enterprise Server Allows Unauthorized Uploads to Repository Migration Exports
Summary
A Missing Authorization vulnerability was identified in GitHub Enterprise Server that allowed an attacker to upload unauthorized content to another user’s repository migration export due to a missing authorization check in the repository migration upload endpoint. By supplying the migration identifier, an attacker could overwrite or replace a victim’s migration archive, potentially causing victims to download attacker-controlled repository data during migration restores or automated imports. An attacker would require authentication to the victim's GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.19.2, 3.18.5, 3.17.11, 3.16.14, 3.15.18, 3.14.23. This vulnerability was reported via the GitHub Bug Bounty program.
Severity ?
6 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:L
CWE
Assigner
References
Impacted products
Vendor Product Version
GitHub Enterprise Server Affected: 3.19.0 , ≤ 3.19.1 (semver)
Affected: 3.18.0 , ≤ 3.18.4 (semver)
Affected: 3.17.0 , ≤ 3.17.10 (semver)
Affected: 3.16.0 , ≤ 3.16.13 (semver)
Affected: 3.15.0 , ≤ 3.15.17 (semver)
Affected: 3.14.0 , ≤ 3.14.22 (semver)
Create a notification for this product.
Credits
ahacker1
Show details on NVD website
To clipboard 

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Sightings

Author Source Type Date

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.



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