CVE-2026-76851
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.8% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.8% in the next 30 days (EPSS).
- Severity: 7.7 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.8% · EPSS, next 30 days
- Weakness
- CWE-918 · Server-side request forgery
- Record status
- Analyzed
Affected
- GitHub Enterprise Server < 3.17.20
- GitHub Enterprise Server < 3.18.14
- GitHub Enterprise Server < 3.19.11
- GitHub Enterprise Server < 3.20.7
- GitHub Enterprise Server < 3.21.5
Attack profile CVSS 4.0 · 7.7
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- Present
- Privileges needed
- Low
- User interaction
- None
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS: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
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-76851.md and follow it. Check whether this project is affected by CVE-2026-76851. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://docs.github.com/en/[email protected]/admin/release-notes#3.17.20
- https://docs.github.com/en/[email protected]/admin/release-notes#3.18.14
- https://docs.github.com/en/[email protected]/admin/release-notes#3.19.11
- https://docs.github.com/en/[email protected]/admin/release-notes#3.20.7
- https://docs.github.com/en/[email protected]/admin/release-notes#3.21.5
References
- https://docs.github.com/en/[email protected]/admin/release-notes#3.17.20
- https://docs.github.com/en/[email protected]/admin/release-notes#3.18.14
- https://docs.github.com/en/[email protected]/admin/release-notes#3.19.11
- https://docs.github.com/en/[email protected]/admin/release-notes#3.20.7
- https://docs.github.com/en/[email protected]/admin/release-notes#3.21.5