CVE-2026-18730
published 2026-09-01CVE-2026-18730: A server-side request forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to cause the Manage API…
PriorityP353high7.4CVSS 3.1
AVNACHPRNUINSUCHIHAN
EPSS
0.29%
21.9th percentile
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 GitHub Enterprise Server releases in the 3.17, 3.18, 3.19, 3.20, and 3.21 series and was fixed in versions 3.17.21, 3.18.15, 3.19.12, 3.20.8, and 3.21.6. This vulnerability was reported via the GitHub Bug Bounty program.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github | enterprise_server | < 3.17.19 | 3.17.19 |
| github | enterprise_server | >= 3.17.0 < 3.17.* | 3.17.* |
| github | enterprise_server | >= 3.18.0 < 3.18.* | 3.18.* |
| github | enterprise_server | >= 3.18.0 < 3.18.13 | 3.18.13 |
| github | enterprise_server | >= 3.19.0 < 3.19.* | 3.19.* |
| github | enterprise_server | >= 3.19.0 < 3.19.10 | 3.19.10 |
| github | enterprise_server | >= 3.20.0 < 3.20.* | 3.20.* |
| github | enterprise_server | >= 3.20.0 < 3.20.6 | 3.20.6 |
| github | enterprise_server | >= 3.21.0 < 3.21.* | 3.21.* |
| github | enterprise_server | >= 3.21.0 < 3.21.4 | 3.21.4 |
CVSS provenance
nvdv3.17.4HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
nvdv4.08.2HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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VulDB
GitHub Enterprise Server up to 3.21.3 Manage API server-side request forgery (EUVD-2026-69714)
vuldb·2026-09-02·CVSS 8.2
CVE-2026-18730 [HIGH] GitHub Enterprise Server up to 3.21.3 Manage API server-side request forgery (EUVD-2026-69714)
A vulnerability categorized as critical has been discovered in GitHub Enterprise Server up to 3.17.18/3.18.12/3.19.9/3.20.5/3.21.3. This affects an unknown function of the component Manage API. The manipulation results in server-side request forgery.
This vulnerability is cataloged as CVE-2026-18730. The attack may be launched remotely. There is no exploit available.
It is advisable to upgrade the affected component.
GHSA
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 a
ghsa_unreviewed·2026-09-02
CVE-2026-18730 [HIGH] CWE-918 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 a
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 vuln
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://docs.github.com/en/[email protected]/admin/release-notes#3.17.21https://docs.github.com/en/[email protected]/admin/release-notes#3.18.15https://docs.github.com/en/[email protected]/admin/release-notes#3.19.12https://docs.github.com/en/[email protected]/admin/release-notes#3.20.8https://docs.github.com/en/[email protected]/admin/release-notes#3.21.6
2026-09-01
Published