Dashboard / CVE-2026-6736

CVE-2026-6736

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 73/100
Published: 2026-05-07 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: X
AT: Present
VC: Low
VI: None
VA: None

Description

An authentication bypass vulnerability was identified in GitHub Enterprise Server that allowed an unauthenticated attacker to create a local user account, bypassing the configured external identity provider. When external authentication was enabled, the signup endpoint did not properly enforce the authentication restriction, allowing account creation and session establishment without identity provider validation. The created account was limited to the default base permissions configured on the instance. Exploitation required network access to a GHES instance configured with an external authentication provider. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.20.2, 3.19.6, 3.18.9, 3.17.15, and 3.16.18.

Weakness Classification (1)

Affected Software (5)

VendorProductVersion
github enterprise_server < 3.16.18
github enterprise_server 3.17.0 – 3.17.15
github enterprise_server 3.18.0 – 3.18.9
github enterprise_server 3.19.0 – 3.19.6
github enterprise_server 3.20.0 – 3.20.2

References & Advisories (5)

Bug Bounty Relevance

73 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

6.3 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/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

EPSS — Exploitation Probability

0.27%
Raw Score 0.002660
Percentile 18.5%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00266
2026-10-28
0.00266

Intelligence Sources

nvd ref →

External Links