CVE-2026-85595

Traefik versions before v2.11.55 and versions v3.0.0 through v3.7.10 contain an authentication bypass vulnerability in the digestAuth middleware where unknown usernames receive an empty secret instead of rejection. Attackers can compute a valid digest response using the empty secret and arbitrary credentials to bypass authentication on any digestAuth-protected route without a valid username or password.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/traefik/traefik/security/advisories/GHSA-5w68-77r2-r64c	Exploit Mitigation Patch Vendor Advisory
https://www.vulncheck.com/advisories/traefik-before-2.11.55-authentication-bypass-via-digestauth	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:traefik:traefik::::::::
	cpe:2.3:a:traefik:traefik::::::::

History

08 Oct 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/traefik/traefik/security/advisories/GHSA-5w68-77r2-r64c - Patch, Vendor Advisory, Exploit, Mitigation~~	() https://github.com/traefik/traefik/security/advisories/GHSA-5w68-77r2-r64c - Exploit, Mitigation, Patch, Vendor Advisory

16 Sep 2026, 20:42

Type	Values Removed	Values Added
CPE		cpe:2.3:a:traefik:traefik::::::::
First Time		Traefik Traefik traefik
References	~~() https://github.com/traefik/traefik/security/advisories/GHSA-5w68-77r2-r64c -~~	() https://github.com/traefik/traefik/security/advisories/GHSA-5w68-77r2-r64c - Patch, Vendor Advisory, Exploit, Mitigation
References	~~() https://www.vulncheck.com/advisories/traefik-before-2.11.55-authentication-bypass-via-digestauth -~~	() https://www.vulncheck.com/advisories/traefik-before-2.11.55-authentication-bypass-via-digestauth - Third Party Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8

Information

Published : 2026-09-04 12:17

Updated : 2026-10-08 16:17

NVD link : CVE-2026-85595

Mitre link : CVE-2026-85595

CVE.ORG link : CVE-2026-85595

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-287

Improper Authentication

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