CVE-2026-3854: CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection') in GitHub Enterprise Server
An improper neutralization of special elements vulnerability was identified in GitHub Enterprise Server that allowed an attacker with push access to a repository to achieve remote code execution on the instance. During a git push operation, user-supplied push option values were not properly sanitized before being included in internal service headers. Because the internal header format used a delimiter character that could also appear in user input, an attacker could inject additional metadata fields through crafted push option values. This vulnerability was reported via the GitHub Bug Bounty program and has been fixed in GitHub Enterprise Server versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7 and 3.19.4.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-3854) involves improper neutralization of special elements (CWE-77) in GitHub Enterprise Server. During a git push operation, user-supplied push option values were included in internal service headers without proper sanitization. The internal header format uses a delimiter character that can appear in user input, allowing an attacker with push access to inject additional metadata fields. This injection can lead to remote code execution on the affected server instance. The vulnerability was responsibly disclosed via the GitHub Bug Bounty program and fixed in GitHub Enterprise Server versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7, and 3.19.4.
Potential Impact
An attacker with push access to a repository on an affected GitHub Enterprise Server instance can exploit this vulnerability to achieve remote code execution on the server. This could allow the attacker to execute arbitrary commands with the privileges of the GitHub Enterprise Server process, potentially leading to full compromise of the server instance. There are no known exploits in the wild at the time of this report.
Mitigation Recommendations
This vulnerability has been fixed in GitHub Enterprise Server versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7, and 3.19.4. Users should upgrade affected instances to one of these versions or later to remediate the issue. Patch status is confirmed by the vendor advisory. No additional mitigation steps are indicated.
CVE-2026-3854: CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection') in GitHub Enterprise Server
Description
An improper neutralization of special elements vulnerability was identified in GitHub Enterprise Server that allowed an attacker with push access to a repository to achieve remote code execution on the instance. During a git push operation, user-supplied push option values were not properly sanitized before being included in internal service headers. Because the internal header format used a delimiter character that could also appear in user input, an attacker could inject additional metadata fields through crafted push option values. This vulnerability was reported via the GitHub Bug Bounty program and has been fixed in GitHub Enterprise Server versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7 and 3.19.4.
CVSS v4.0
Score 8.7high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-3854) involves improper neutralization of special elements (CWE-77) in GitHub Enterprise Server. During a git push operation, user-supplied push option values were included in internal service headers without proper sanitization. The internal header format uses a delimiter character that can appear in user input, allowing an attacker with push access to inject additional metadata fields. This injection can lead to remote code execution on the affected server instance. The vulnerability was responsibly disclosed via the GitHub Bug Bounty program and fixed in GitHub Enterprise Server versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7, and 3.19.4.
Potential Impact
An attacker with push access to a repository on an affected GitHub Enterprise Server instance can exploit this vulnerability to achieve remote code execution on the server. This could allow the attacker to execute arbitrary commands with the privileges of the GitHub Enterprise Server process, potentially leading to full compromise of the server instance. There are no known exploits in the wild at the time of this report.
Mitigation Recommendations
This vulnerability has been fixed in GitHub Enterprise Server versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7, and 3.19.4. Users should upgrade affected instances to one of these versions or later to remediate the issue. Patch status is confirmed by the vendor advisory. No additional mitigation steps are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_P
- Date Reserved
- 2026-03-09T20:19:58.513Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 69b059afea502d3aa881750d
Added to database: 3/10/2026, 5:49:35 PM
Last enriched: 4/29/2026, 5:47:18 AM
Last updated: 6/12/2026, 12:19:30 PM
Views: 445
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