CVE-2026-5512
Received Received - Intake
Improper Authorization in GitHub Enterprise Server Exposes Private Repo Names

Publication date: 2026-04-21

Last updated on: 2026-04-29

Assigner: GitHub, Inc. (Products Only)

Description
An improper authorization vulnerability was identified in GitHub Enterprise Server that allowed an authenticated attacker to determine the names of private repositories by their numeric ID. The mobile upload policy API endpoint did not perform an early authorization check, and validation error messages included the full repository name for repositories the caller did not have access to. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.20.1, 3.19.5, 3.18.8, 3.17.14, 3.16.17, 3.15.21, and 3.14.26. This vulnerability was reported via the GitHub Bug Bounty program.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-04-21
Last Modified
2026-04-29
Generated
2026-05-07
AI Q&A
2026-04-22
EPSS Evaluated
2026-05-05
NVD
EUVD
Affected Vendors & Products
Showing 7 associated CPEs
Vendor Product Version / Range
github enterprise_server to 3.14.26 (exc)
github enterprise_server From 3.15.0 (inc) to 3.15.21 (exc)
github enterprise_server From 3.16.0 (inc) to 3.16.17 (exc)
github enterprise_server From 3.17.0 (inc) to 3.17.14 (exc)
github enterprise_server From 3.18.0 (inc) to 3.18.8 (exc)
github enterprise_server From 3.19.0 (inc) to 3.19.5 (exc)
github enterprise_server 3.20.0
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-201 The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?

This vulnerability is an improper authorization issue in GitHub Enterprise Server. It allows an authenticated attacker to discover the names of private repositories by their numeric IDs. The problem occurs because the mobile upload policy API endpoint does not perform an early authorization check, and validation error messages reveal the full repository names even when the caller does not have access to those repositories.


How can this vulnerability impact me? :

The vulnerability can impact you by exposing the names of private repositories that should remain confidential. An attacker with authenticated access could use this flaw to gather information about private repositories, potentially leading to further targeted attacks or information leakage.


What immediate steps should I take to mitigate this vulnerability?

To mitigate this vulnerability, you should upgrade your GitHub Enterprise Server to one of the fixed versions: 3.20.1, 3.19.5, 3.18.8, 3.17.14, 3.16.17, 3.15.21, or 3.14.26.


Ask Our AI Assistant
Need more information? Ask your question to get an AI reply (Powered by our expertise)
0/70
EPSS Chart