CVE-2026-8606: CWE-918 Server-Side request forgery (SSRF) in GitHub Enterprise Server
CVE-2026-8606 is a Server-Side Request Forgery (SSRF) vulnerability in GitHub Enterprise Server affecting versions prior to 3. 21. 1. It allows attackers to make the server send HTTP requests to internal services via the security advisories package lookup feature. Exploitation can leak sensitive environment variables such as signing secrets and private keys by analyzing response timing. The vulnerability requires GitHub Packages to be enabled and can be exploited without authentication on non-private mode instances; otherwise, any authenticated user can exploit it. The issue was fixed in versions 3. 20. 3, 3. 19.
AI Analysis
Technical Summary
This vulnerability in GitHub Enterprise Server (CVE-2026-8606) is a Server-Side Request Forgery (CWE-918) that leverages the security advisories package lookup feature to cause the server to issue HTTP requests to internal management services. By measuring response timing, an attacker can infer sensitive environment variables including signing secrets and private keys. The vulnerability affects all versions before 3.21.1 and requires GitHub Packages to be enabled. Exploitation is possible without authentication on instances not running in private mode; otherwise, any authenticated user can exploit it. The vulnerability was reported through the GitHub Bug Bounty program and fixed in multiple patch releases across affected versions.
Potential Impact
Successful exploitation allows an attacker to perform SSRF attacks that can reveal sensitive environment variables such as signing secrets and private keys. This can lead to further compromise of the server or its environment. The vulnerability is rated high severity with a CVSS 4.0 score of 7. No known exploits in the wild have been reported.
Mitigation Recommendations
Fixes for this vulnerability are available in GitHub Enterprise Server versions 3.20.3, 3.19.7, 3.18.10, 3.17.16, and 3.16.19. Users should upgrade affected instances to one of these versions or later to remediate the issue. Since this is not a cloud service, remediation depends on applying these official patches. Patch status is confirmed by the vendor advisory embedded in the description.
CVE-2026-8606: CWE-918 Server-Side request forgery (SSRF) in GitHub Enterprise Server
Description
CVE-2026-8606 is a Server-Side Request Forgery (SSRF) vulnerability in GitHub Enterprise Server affecting versions prior to 3. 21. 1. It allows attackers to make the server send HTTP requests to internal services via the security advisories package lookup feature. Exploitation can leak sensitive environment variables such as signing secrets and private keys by analyzing response timing. The vulnerability requires GitHub Packages to be enabled and can be exploited without authentication on non-private mode instances; otherwise, any authenticated user can exploit it. The issue was fixed in versions 3. 20. 3, 3. 19.
CVSS v4.0
Score 7.0high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in GitHub Enterprise Server (CVE-2026-8606) is a Server-Side Request Forgery (CWE-918) that leverages the security advisories package lookup feature to cause the server to issue HTTP requests to internal management services. By measuring response timing, an attacker can infer sensitive environment variables including signing secrets and private keys. The vulnerability affects all versions before 3.21.1 and requires GitHub Packages to be enabled. Exploitation is possible without authentication on instances not running in private mode; otherwise, any authenticated user can exploit it. The vulnerability was reported through the GitHub Bug Bounty program and fixed in multiple patch releases across affected versions.
Potential Impact
Successful exploitation allows an attacker to perform SSRF attacks that can reveal sensitive environment variables such as signing secrets and private keys. This can lead to further compromise of the server or its environment. The vulnerability is rated high severity with a CVSS 4.0 score of 7. No known exploits in the wild have been reported.
Mitigation Recommendations
Fixes for this vulnerability are available in GitHub Enterprise Server versions 3.20.3, 3.19.7, 3.18.10, 3.17.16, and 3.16.19. Users should upgrade affected instances to one of these versions or later to remediate the issue. Since this is not a cloud service, remediation depends on applying these official patches. Patch status is confirmed by the vendor advisory embedded in the description.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_P
- Date Reserved
- 2026-05-14T15:28:24.899Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a16385ae29bf47b5077ecb4
Added to database: 5/27/2026, 12:18:34 AM
Last enriched: 5/27/2026, 12:33:36 AM
Last updated: 5/27/2026, 1:25:27 AM
Views: 3
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