CVE-2026-88009 Traefik: Rootless HTTP/1 request-target routes as "/" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging
Attackers can bypass path-scoped routing, authorization, and logging in Traefik by sending rootless HTTP/1 request targets, potentially accessing unauthorized resources.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-88009?
CVE-2026-88009 is a high-severity vulnerability in Traefik Traefik, published on 10 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.57, and 3.7.13, Traefik accepts a rootless HTTP/1 request target that Go stores in URL.Opaque while leaving URL.Path empty. The rewriteRequestBuilder path evaluates routing, path sanitization, forwardAuth, encodedCharacters, and access logging against a path normalized to / but forwards URL.Opaque verbatim to the backend, allowing cross-vhost routing bypass, path-scoped authorization bypass, and access-log evasion when the backend interprets the opaque target as a path. This issue is fixed in 2.11.57 and 3.7.13.
Which versions are affected by CVE-2026-88009?
7 open source packages ship an affected version, including github.com/traefik/traefik/v2, github.com/traefik/traefik and github.com/traefik/traefik/v3. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/traefik/traefik/v2 Go | All versions | 2.11.57 |
github.com/traefik/traefik/v2 Go | All versions | 2.11.57 |
github.com/traefik/traefik/v2 Go | All versions | 2.11.57 |
github.com/traefik/traefik Go | All versions | None |
github.com/traefik/traefik/v3 Go | From 3.0.0 | 3.7.13 |
github.com/traefik/traefik/v3 Go | From 3.0.0 | 3.7.13 |
1 more packages
github.com/traefik/traefik/v3 Go | From 3.0.0 | 3.7.13 |
Products include Traefik Traefik.
How do I fix CVE-2026-88009?
Upgrade github.com/traefik/traefik/v2 to 2.11.57 or later.
Is CVE-2026-88009 being exploited?
There is no known exploitation of CVE-2026-88009 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Traefik Traefik
- CVE-2024-45410 HTTP client can remove the X-Forwarded headers in Traefik
- CVE-2026-88877 Traefik v3.7.0 Authentication Bypass via from-to-www-redirect
- CVE-2026-85595 Traefik before v2.11.55 and v3.0.0 through v3.7.10 Authentication Bypass via digestAuth
- CVE-2026-88007 Traefik HTTP/3 Backend NTLM Connection Reuse
- CVE-2025-32431 Traefik has a possible vulnerability with the path matchers
Sources
Also known as ECHO-4418-b246-3ebf, GHSA-f52w-8j3h-j724, GO-2026-6465, MINI-8xxv-cmpq-xwpx, MINI-gjmm-f26x-wchj, MINI-p89f-3c69-v3v7.