CVE-2026-4821

An improper neutralization of special elements vulnerability was identified in GitHub Enterprise Server that allowed an authenticated Management Console administrator to execute arbitrary OS commands via shell metacharacter injection in proxy configuration fields such as http_proxy. Exploitation of this vulnerability required access to the GitHub Enterprise Server instance and administrator privileges to the Management Console. 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, 3.14.26. This vulnerability was reported via the GitHub Bug Bounty program.

The following products are affected by CVE-2026-4821 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-4821.

URL	Resource
https://docs.github.com/en/[email protected]/admin/release-notes#3.14.24
https://docs.github.com/en/[email protected]/admin/release-notes#3.15.21
https://docs.github.com/en/[email protected]/admin/release-notes#3.16.17
https://docs.github.com/en/[email protected]/admin/release-notes#3.17.14
https://docs.github.com/en/[email protected]/admin/release-notes#3.18.8
https://docs.github.com/en/[email protected]/admin/release-notes#3.19.5
https://docs.github.com/en/[email protected]/admin/release-notes#3.20.1