---
title: "CVE-2026-65600: Traefik: Authentication Bypass via Path Traversal in ReplacePathRegex Middleware"
url: https://erroneo.us/security/cve/CVE-2026-65600/
description: "CVE-2026-65600 (github.com/traefik/traefik/v2 (Go)): Traefik versions = v3.6.0 = v3.7.0"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-07-22
date_modified: 2026-10-08
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-65600"
kev: false
cvss: 7.8
epss: 0.00621
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-65600: Traefik: Authentication Bypass via Path Traversal in ReplacePathRegex Middleware

**Signal:** Normal patch cycle. No exploitation signal; fix it in your next routine update if you are affected. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.6% , percentile 49: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 49% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes github.com/traefik/traefik/v2 (Go) <= 2.11.51, fixed in 2.11.52 ; github.com/traefik/traefik/v3 (Go) <= 3.6.22, fixed in 3.6.23 ; github.com/traefik/traefik/v3 (Go) >= 3.7.0, <= 3.7.6, fixed in 3.7.7 ; github.com/traefik/traefik (Go) <= 1.7.34, no fixed version listed . Check your lockfile, including transitive dependencies.

## What it is

Traefik versions = v3.6.0 = v3.7.0

## Affected packages

- Go `github.com/traefik/traefik/v2` <= 2.11.51 → fixed: 2.11.52
- Go `github.com/traefik/traefik/v3` <= 3.6.22 → fixed: 3.6.23
- Go `github.com/traefik/traefik/v3` >= 3.7.0, <= 3.7.6 → fixed: 3.7.7
- Go `github.com/traefik/traefik` <= 1.7.34 → fixed: none listed

## Affected products (CVE record)

- traefik traefik: < 2.11.52
- traefik traefik: 3.6.0 < 3.6.23
- traefik traefik: 3.7.0 < 3.7.7

## Severity

- VulnCheck CVSS 4.0: 7.8 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N`
- GitHub CVSS 3.1: 9.1 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 0.62% probability of exploitation activity in the next 30 days; percentile 49.

## Sources

- [GitHub Security Advisory (GHSA-cxjq-mrr5-89rv)](https://github.com/traefik/traefik/security/advisories/GHSA-cxjq-mrr5-89rv)
- [GitHub Advisory GHSA-cxjq-mrr5-89rv](https://github.com/advisories/GHSA-cxjq-mrr5-89rv)
- [CVE.org record CVE-2026-65600](https://www.cve.org/CVERecord?id=CVE-2026-65600)
- [NVD entry CVE-2026-65600](https://nvd.nist.gov/vuln/detail/CVE-2026-65600)
- [VulnCheck Advisory: Traefik before v2.11.52 Authentication Bypass via ReplacePathRegex](https://www.vulncheck.com/advisories/traefik-before-authentication-bypass-via-replacepathregex)
- [github.com](https://github.com/traefik/traefik/commit/3f10dd442479530560f010167cac2947676d9b29)
- [github.com](https://github.com/traefik/traefik/releases/tag/v2.11.52)
- [github.com](https://github.com/traefik/traefik/releases/tag/v3.6.23)
- [github.com](https://github.com/traefik/traefik/releases/tag/v3.7.7)

---
Source page: https://erroneo.us/security/cve/CVE-2026-65600/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt