Traefik before v2.11.52 Authentication Bypass via ReplacePathRegex

Description

Traefik versions <= v2.11.51, >= v3.6.0 <= v3.6.22, and >= v3.7.0 <= v3.7.6 contain an authentication bypass via path traversal in the ReplacePathRegex middleware. When ReplacePathRegex is configured with a regex that captures user-controlled path segments without a mandatory path separator (e.g. regex "^/api(.*)", replacement "/$1"), the middleware forwards the replaced path to the backend without validating that it matches its normalized form. An unauthenticated remote attacker can send a crafted request (e.g. GET /api../admin) that produces an un-normalized path such as /../admin, which a backend that normalizes paths resolves to a protected route, bypassing authentication middleware. Fixed in v2.11.52, v3.6.23, and v3.7.7.

Scores

EPSS (exploitation in 30 days)

0.62% · top 50% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: yes · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.

Weakness

• CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (opens in a new tab)All about CWE-22 and its CVEs

Affected products

• traefik · traefik

  • affected < 2.11.52
  • unaffected 2.11.52

• traefik · traefik

  • affected 3.6.0 – < 3.6.23
  • unaffected 3.6.23

• traefik · traefik

  • affected 3.7.0 – < 3.7.7
  • unaffected 3.7.7

Affected packages

From reviewed advisories of the GitHub Advisory Database.

• Gogithub.com/traefik/traefikGHSA-cxjq-mrr5-89rv (opens in a new tab)
• Gogithub.com/traefik/traefik/v2GHSA-cxjq-mrr5-89rv (opens in a new tab)
• Gogithub.com/traefik/traefik/v3GHSA-cxjq-mrr5-89rv (opens in a new tab)

References (2)

• GitHub Security Advisory (GHSA-cxjq-mrr5-89rv) (opens in a new tab)vendor-advisory
• VulnCheck Advisory: Traefik before v2.11.52 Authentication Bypass via ReplacePathRegex (opens in a new tab)third-party-advisory

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisory GHSA-cxjq-mrr5-89rv (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-65600](https://trackcve.app/badge/CVE-2026-65600.svg)](https://trackcve.app/cve/CVE-2026-65600)

Record last updated 8 Oct 2026, 15:23 UTC.