CVE-2026-88009
Traefik: Rootless HTTP/1 request-target routes as "/" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging
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.
INFO
Published Date :
Sept. 10, 2026, 4:18 p.m.
Last Modified :
Sept. 14, 2026, 7:59 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update Traefik to version 2.11.57 or 3.7.13.
- Verify request routing and authorization after update.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-88009.
| URL | Resource |
|---|---|
| https://github.com/traefik/traefik/commit/58d1e9ca204526823211e30fd4634101c59d58e9 | Patch |
| https://github.com/traefik/traefik/pull/13796 | Issue Tracking Patch |
| https://github.com/traefik/traefik/releases/tag/v2.11.57 | Release Notes |
| https://github.com/traefik/traefik/releases/tag/v3.7.13 | Release Notes |
| https://github.com/traefik/traefik/security/advisories/GHSA-f52w-8j3h-j724 | Patch Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-88009 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-88009
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-88009 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-88009 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Sep. 14, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N Added CPE Configuration OR *cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* versions up to (excluding) 2.11.57 *cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* versions from (including) 3.0.0 up to (excluding) 3.7.13 Added Reference Type GitHub, Inc.: https://github.com/traefik/traefik/commit/58d1e9ca204526823211e30fd4634101c59d58e9 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/traefik/traefik/pull/13796 Types: Issue Tracking, Patch Added Reference Type GitHub, Inc.: https://github.com/traefik/traefik/releases/tag/v2.11.57 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/traefik/traefik/releases/tag/v3.7.13 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/traefik/traefik/security/advisories/GHSA-f52w-8j3h-j724 Types: Patch, Vendor Advisory -
New CVE Received by [email protected]
Sep. 10, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/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 Added CWE CWE-444 Added CWE CWE-1286 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/88xxx/CVE-2026-88009.json">CVE-2026-88009</a> Added Reference https://github.com/traefik/traefik/commit/58d1e9ca204526823211e30fd4634101c59d58e9 Added Reference https://github.com/traefik/traefik/pull/13796 Added Reference https://github.com/traefik/traefik/releases/tag/v2.11.57 Added Reference https://github.com/traefik/traefik/releases/tag/v3.7.13 Added Reference https://github.com/traefik/traefik/security/advisories/GHSA-f52w-8j3h-j724 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 10, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-88009', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-10T15:39:54.256441Z'}