Vulnerability in Github Enterprise Server
CVE-2026-4296
An incorrect regular expression vulnerability was identified in GitHub Enterprise Server that allowed an attacker to bypass OAuth redirect URI validation. An attacker with knowledge of a first-party OAuth application's registered callback…
EPSS: 0.001 (15.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
Affected products
- Github Enterprise Server — versions 3.14.0, 3.15.0, 3.16.0
- Github Enterprise_server — versions 3.20.0
Weakness classification (CWE)
References
- product-cna@github.com (release-notes, Release Notes, Vendor Advisory)
- product-cna@github.com (release-notes, Release Notes, Vendor Advisory)
- product-cna@github.com (release-notes, Release Notes, Vendor Advisory)
- product-cna@github.com (release-notes, Release Notes, Vendor Advisory)
- product-cna@github.com (release-notes, Release Notes, Vendor Advisory)
- product-cna@github.com (release-notes, Release Notes, Vendor Advisory)
- product-cna@github.com (release-notes, Release Notes, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-4296?
- CVE-2026-4296 is a high-severity vulnerability in Github Enterprise Server, classified under Incorrect Regular Expression. CVSS score: 8.8/10. Published 2026-04-21.
- How severe is CVE-2026-4296?
- High severity. CVSS v3 base score is 8.8 out of 10.