Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

High severity, with a CVSS score of 7.8, published 22 July 2026.

Which products and versions are affected?

github.com/traefik/traefik/v2 (Go) = v3.6.0 = v3.7.0 <= v3.7.6.

Is there a fix for This vulnerability?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is This vulnerability attacked?

It is attacked over the network, in a hosted service.

Check whether you run github.com/traefik/traefik/v2 (Go) or Traefik Labs Traefik Proxy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Traefik auth bypass via path traversal in ReplacePathRegex middleware

Q: Is there a fix for This vulnerability?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

Q: How is This vulnerability attacked?

It is attacked over the network, in a hosted service.

Q: Am I affected?

Check whether you run github.com/traefik/traefik/v2 (Go) or Traefik Labs Traefik Proxy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Severity: high · CVSS 7.8 · Published 2026-07-22

Traefik, a popular open-source edge router and load balancer, is vulnerable to a security flaw that allows attackers to bypass authentication. By sending specially crafted web requests, an unauthorized user can trick the system into granting access to protected internal resources or administrative panels. This could lead to unauthorized data access or full compromise of backend services managed by Traefik.

Technologies: github.com/traefik/traefik/v2 (Go), Traefik Labs Traefik Proxy. Vendors: Go, Traefik Labs.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: High severity, with a CVSS score of 7.8, published 22 July 2026.
Which products and versions are affected?: github.com/traefik/traefik/v2 (Go) <= 2.11.51; Traefik Labs Traefik Proxy <= v2.11.51, >= v3.6.0 <= v3.6.22, >= v3.7.0 <= v3.7.6.
Is there a fix for This vulnerability?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is This vulnerability attacked?: It is attacked over the network, in a hosted service.
Am I affected?: Check whether you run github.com/traefik/traefik/v2 (Go) or Traefik Labs Traefik Proxy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A path traversal vulnerability exists in Traefik's ReplacePathRegex middleware when configured with regular expressions that capture user-controlled path segments without mandatory separators (e.g., '^/api(.*)'). The middleware fails to validate that the resulting replaced path matches its normalized form before forwarding it to the backend. An unauthenticated remote attacker can exploit this by sending a crafted request like 'GET /api../admin', which resolves to an un-normalized path such as '/../admin'. If the backend service normalizes this path, it may grant access to protected routes, effectively bypassing Traefik's authentication middleware. The issue is fixed in versions 2.11.52, 3.6.23, and 3.7.7.

Affected products

Traefik Labs Traefik <= v2.11.51, >= v3.6.0 <= v3.6.22, >= v3.7.0 <= v3.7.6

Timeline

2026-07-22: disclosed
2026-07-22: advisory
2026-08-06: other: Advisory withdrawn as duplicate of GHSA-cxjq-mrr5-89rv

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.