A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.19, 3.18.13, 3.19.10, 3.20.6, and 3.21.4. This vulnerability was reported via the GitHub Bug Bounty program.
Metrics
Affected Vendors & Products
References
History
Wed, 02 Sep 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Tue, 01 Sep 2026 23:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Github
Github enterprise Server |
|
| Vendors & Products |
Github
Github enterprise Server |
Tue, 01 Sep 2026 22:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API to send crafted outbound requests to an attacker-controlled host. An unauthenticated endpoint parsed an attacker-supplied cluster configuration and issued gateway-to-agent requests whose HMAC authenticated only a timestamp, not the request path or body. An attacker positioned to intercept the outbound request could capture this token and replay it against privileged management agent endpoints. High-availability deployments were not affected due to a topology restriction. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.19, 3.18.13, 3.19.10, 3.20.6, and 3.21.4. This vulnerability was reported via the GitHub Bug Bounty program. | |
| Title | Server-side request forgery vulnerability in GitHub Enterprise Server Manage API leaked a replayable gateway-agent bearer token | |
| Weaknesses | CWE-918 | |
| References |
|
|
| Metrics |
cvssV4_0
|
Status: PUBLISHED
Assigner: GitHub_P
Published: 2026-09-01T21:54:58.397Z
Updated: 2026-09-02T13:19:21.618Z
Reserved: 2026-08-03T18:33:43.917Z
Link: CVE-2026-18730
Updated: 2026-09-02T13:19:17.995Z
Status : Awaiting Analysis
Published: 2026-09-01T22:17:10.850
Modified: 2026-09-03T16:43:15.293
Link: CVE-2026-18730
No data.