Vulnerability · Published Mar 3, 2021 · Assigned by GitHub_P
CVE-2021-22861Improper access control in GitHub Enterprise Server leading to unauthorized write access to forkable repositories
Medium 6.5
In plain English
A medium-severity security flaw in GitHub Enterprise Server from GitHub. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.0% (higher than 61% of all known vulnerabilities).
Official description
An improper access control vulnerability was identified in GitHub Enterprise Server that allowed authenticated users of the instance to gain write access to unauthorized repositories via specifically crafted pull requests and REST API requests. An attacker would need to be able to fork the targeted repository, a setting that is disabled by default for organization owned private repositories. Branch protections such as required pull request reviews or status checks would prevent unauthorized commits from being merged without further review or validation. This vulnerability affected all versions of GitHub Enterprise Server since 2.4.21 and was fixed in versions 2.20.24, 2.21.15, 2.22.7 and 3.0.1. This vulnerability was reported via the GitHub Bug Bounty program.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| GitHub | GitHub Enterprise Server | 2.20 – before 2.20.242.21 – before 2.21.152.22 – before 2.22.73.0 – before 3.0.1 |
Weakness: CWE-285
References
- https://docs.github.com/en/enterprise-server%402.20/admin/release-notes#2.20.24 x_refsource_MISC
- https://docs.github.com/en/enterprise-server%402.21/admin/release-notes#2.21.15 x_refsource_MISC
- https://docs.github.com/en/enterprise-server%402.22/admin/release-notes#2.22.7 x_refsource_MISC
- https://docs.github.com/en/enterprise-server%403.0/admin/release-notes#3.0.1 x_refsource_MISC