CVE-2025-66490

Dec. 9, 2025, 6:37 p.m.

6.9
Medium

Description

Traefik is an HTTP reverse proxy and load balancer. For versions prior to 2.11.32 and 2.11.31 through 3.6.2, requests using PathPrefix, Path or PathRegex matchers can bypass path normalization. When Traefik uses path-based routing, requests containing URL-encoded restricted characters (/, \, Null, ;, ?, #) can bypass the middleware chain and reach unintended backends. For example, a request to http://mydomain.example.com/admin%2F could reach service-a without triggering my-security-middleware, bypassing security controls for the /admin/ path. This issue is fixed in versions 2.11.32 and 3.6.3.

Product(s) Impacted

Vendor Product Versions
Traefik
  • Traefik
  • <2.11.32, 2.11.31-3.6.2

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-436
Interpretation Conflict
Product A handles inputs or steps differently than Product B, which causes A to perform incorrect actions based on its perception of B's state.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a traefik traefik <2.11.32 / / / / / / /
a traefik traefik 2.11.31-3.6.2 / / / / / / /

References

https://github.com/traefik/traefik/releases/tag/v2.11.32
https://github.com/traefik/traefik/releases/tag/v3.6.4
https://github.com/traefik/traefik/security/advisories/GHSA-gm3x-23wp-hc2c
https://github.com/traefik/traefik/security/advisories/GHSA-gm3x-23wp-hc2c

Tags

security-advisories@github.com
CWE-436
2025-12-09
CVE-2025-66490

CVSS Score

6.9 / 10

CVSS Data - 4.0

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Attack Requirements: NONE
  • Privileges Required: NONE
  • User Interaction: NONE
  • Scope:
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: NONE
  • Exploit Maturity: NOT_DEFINED

    • CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/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

    View Vector String

Timeline

Published: Dec. 9, 2025, 1:16 a.m.
Last Modified: Dec. 9, 2025, 6:37 p.m.

Status : Awaiting Analysis

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

security-advisories@github.com

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.