CVE-2026-4821

7.2 HIGH
Published: April 21, 2026 Modified: April 29, 2026
View on NVD

Description

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.24
Source: product-cna@github.com
Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.21
Source: product-cna@github.com
Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.17
Source: product-cna@github.com
Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.14
Source: product-cna@github.com
Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.8
Source: product-cna@github.com
Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.5
Source: product-cna@github.com
Release Notes Vendor Advisory
https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.1
Source: product-cna@github.com
Release Notes Vendor Advisory

7 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.2 / 10.0
EPSS (Exploit Probability)
0.0%
11th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

github