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.
References
| Link | Resource |
|---|---|
| https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.24 | Release Notes Vendor Advisory |
| https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.21 | Release Notes Vendor Advisory |
| https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.17 | Release Notes Vendor Advisory |
| https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.14 | Release Notes Vendor Advisory |
| https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.8 | Release Notes Vendor Advisory |
| https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.5 | Release Notes Vendor Advisory |
| https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.1 | Release Notes Vendor Advisory |
Configurations
Configuration 1 (hide)
|
History
29 Apr 2026, 12:36
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.2 |
| First Time |
Github
Github enterprise Server |
|
| CPE | cpe:2.3:a:github:enterprise_server:3.20.0:*:*:*:*:*:*:* cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* |
|
| References | () https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.24 - Release Notes, Vendor Advisory | |
| References | () https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.21 - Release Notes, Vendor Advisory | |
| References | () https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.17 - Release Notes, Vendor Advisory | |
| References | () https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.14 - Release Notes, Vendor Advisory | |
| References | () https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.8 - Release Notes, Vendor Advisory | |
| References | () https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.5 - Release Notes, Vendor Advisory | |
| References | () https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.1 - Release Notes, Vendor Advisory |
21 Apr 2026, 23:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-21 23:16
Updated : 2026-04-29 12:36
NVD link : CVE-2026-4821
Mitre link : CVE-2026-4821
CVE.ORG link : CVE-2026-4821
JSON object : View
Products Affected
github
- enterprise_server
CWE
CWE-78
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')