CVEs / CVE-2026-3854
CVE-2026-3854: GitHub Enterprise Server vulnerability
- high 8.8 CVSS 3.1 (NVD)
- EPSS 39.7% chance of exploitation in the next 30 days, higher than 98% of CVEs (30 Oct 2026)
- Last changed at its sources
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Description
An improper neutralization of special elements vulnerability was identified in GitHub Enterprise Server that allowed an attacker with push access to a repository to achieve remote code execution on the instance. During a git push operation, user-supplied push option values were not properly sanitized before being included in internal service headers. Because the internal header format used a delimiter character that could also appear in user input, an attacker could inject additional metadata fields through crafted push option values. This vulnerability was reported via the GitHub Bug Bounty program and has been fixed in GitHub Enterprise Server versions 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.7 and 3.19.4.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| GitHub Enterprise Server | from 3.14.0, up to and including 3.14.24 | — |
| GitHub Enterprise Server | from 3.15.0, up to and including 3.15.19 | — |
| GitHub Enterprise Server | from 3.16.0, up to and including 3.16.15 | — |
| GitHub Enterprise Server | from 3.17.0, up to and including 3.17.12 | — |
| GitHub Enterprise Server | from 3.18.0, up to and including 3.18.6 | — |
| GitHub Enterprise Server | from 3.19.0, up to and including 3.19.3 | — |
Exploitation
Not in the CISA Known Exploited Vulnerabilities catalog as of 30 Oct 2026.
Severity
| CVSS 3.1 | 8.8 highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-77 |
References
- CVE-2026-3854 on NVD
- https://docs.github.com/en/[email protected]/admin/release-notes#3.14.25
- https://docs.github.com/en/[email protected]/admin/release-notes#3.15.20
- https://docs.github.com/en/[email protected]/admin/release-notes#3.16.16
- https://docs.github.com/en/[email protected]/admin/release-notes#3.17.13
- https://docs.github.com/en/[email protected]/admin/release-notes#3.18.7
- https://docs.github.com/en/[email protected]/admin/release-notes#3.19.4
- https://www.wiz.io/blog/github-rce-vulnerability-cve-2026-3854
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.