CVE-2026-76851
published 2026-09-01CVE-2026-76851: A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed remote code execution on the instance. Insufficient…
PriorityP264high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EPSS
0.51%
42.5th percentile
A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed remote code execution on the instance. Insufficient network isolation allowed malicious pre-receive hook code to impersonate an internal service and redirect trusted internal requests to a privileged service, leading to elevated code execution. Exploitation required pre-receive hook networking to be enabled and either site administrator privileges or write access to a repository containing a configured pre-receive hook. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.20, 3.18.14, 3.19.11, 3.20.7, and 3.21.5. This vulnerability was reported via the GitHub Bug Bounty program.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github | enterprise_server | < 3.17.20 | 3.17.20 |
| github | enterprise_server | 3.17.0 – 3.17.19 | — |
| github | enterprise_server | >= 3.18.0 < 3.18.14 | 3.18.14 |
| github | enterprise_server | 3.18.0 – 3.18.13 | — |
| github | enterprise_server | >= 3.19.0 < 3.19.11 | 3.19.11 |
| github | enterprise_server | 3.19.0 – 3.19.10 | — |
| github | enterprise_server | >= 3.20.0 < 3.20.7 | 3.20.7 |
| github | enterprise_server | 3.20.0 – 3.20.6 | — |
| github | enterprise_server | >= 3.21.0 < 3.21.5 | 3.21.5 |
| github | enterprise_server | 3.21.0 – 3.21.4 | — |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv4.07.7HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/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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GHSA
A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed remote code execution on the instance.
ghsa_unreviewed·2026-09-02
CVE-2026-76851 [HIGH] CWE-918 A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed remote code execution on the instance.
A Server-Side Request Forgery (SSRF) vulnerability was identified in GitHub Enterprise Server that allowed remote code execution on the instance. Insufficient network isolation allowed malicious pre-receive hook code to impersonate an internal service and redirect trusted internal requests to a privileged service, leading to elevated code execution. Exploitation required pre-receive hook networking to be enabled and either site administrator privileges or write access to a repository containing a configured pre-receive hook. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.17.20, 3.18.14, 3.19.11, 3.20.7, and 3.21.5. This vulnerability was reported via the GitHub Bug Bounty program.
VulDB
GitHub Enterprise Server up to 3.21.4 Pre-receive Hook server-side request forgery (EUVD-2026-69716)
vuldb·2026-09-02·CVSS 7.7
CVE-2026-76851 [HIGH] GitHub Enterprise Server up to 3.21.4 Pre-receive Hook server-side request forgery (EUVD-2026-69716)
A vulnerability was found in GitHub Enterprise Server up to 3.17.19/3.18.13/3.19.10/3.20.6/3.21.4. It has been rated as critical. The impacted element is an unknown function of the component Pre-receive Hook. The manipulation leads to server-side request forgery.
This vulnerability is listed as CVE-2026-76851. The attack may be initiated remotely. There is no available exploit.
Upgrading the affected component is advised.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://docs.github.com/en/[email protected]/admin/release-notes#3.17.20https://docs.github.com/en/[email protected]/admin/release-notes#3.18.14https://docs.github.com/en/[email protected]/admin/release-notes#3.19.11https://docs.github.com/en/[email protected]/admin/release-notes#3.20.7https://docs.github.com/en/[email protected]/admin/release-notes#3.21.5
2026-09-01
Published