CVE-2026-4296An incorrect regular expression vulnerability was identified in GitHub Enterprise Server that allowed an attacker to bypass OAuth redirect URI validation.
Updated under an hour ago ()
Does this affect you?
It affects github enterprise_server. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
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 URL could craft a malicious authorization link that, when clicked by a victim, would redirect the OAuth authorization code to an attacker-controlled domain. This could allow the attacker to gain unauthorized access to the victim's account with the scopes granted to the OAuth application. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.20.1, 3.19.5, 3.18.8, 3.17.14, 3.16.17, 3.15.21, 3.14.26. This vulnerability was reported via the GitHub Bug Bounty program.
- CVSS
- 8.8 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Weakness (CWE)
- CWE-185
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Not given
- NVD analysis
- Analyzed
- Record last updated
- Jun 17, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
github enterprise_server github:enterprise_server | before 3.14.26; from 3.15.0 before 3.15.21; from 3.16.0 before 3.16.17; from 3.17.0 before 3.17.14; from 3.18.0 before 3.18.8; from 3.19.0 before 3.19.5; 3.20.0 | NVD |
References
- https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.26release-notes, vendor-advisory
- https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.21release-notes, vendor-advisory
- https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.17release-notes, vendor-advisory
- https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.14release-notes, vendor-advisory
- https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.8release-notes, vendor-advisory
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.5release-notes, vendor-advisory
- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.1release-notes, vendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.