CVE-2026-65600
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.
INFO
Published Date :
July 22, 2026, 12:18 p.m.
Last Modified :
Aug. 6, 2026, 3:42 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 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update Traefik to v2.11.52 or later.
- Update Traefik to v3.6.23 or later.
- Update Traefik to v3.7.7 or later.
- Review ReplacePathRegex middleware configurations.
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-2026-65600.
| URL | Resource |
|---|---|
| https://github.com/traefik/traefik/security/advisories/GHSA-cxjq-mrr5-89rv | Vendor Advisory Patch |
| https://www.vulncheck.com/advisories/traefik-before-authentication-bypass-via-replacepathregex | Third Party 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-2026-65600 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-2026-65600
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-2026-65600 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-65600 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]
Aug. 06, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Added CPE Configuration OR *cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* versions up to (excluding) 2.11.52 *cpe:2.3:a:traefik:traefik:*:-:*:*:*:*:*:* versions from (including) 3.6.0 up to (excluding) 3.6.23 *cpe:2.3:a:traefik:traefik:*:-:*:*:*:*:*:* versions from (including) 3.7.0 up to (excluding) 3.7.7 Added Reference Type VulnCheck: https://github.com/traefik/traefik/security/advisories/GHSA-cxjq-mrr5-89rv Types: Patch, Vendor Advisory Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/traefik-before-authentication-bypass-via-replacepathregex Types: Third Party Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 23, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-65600', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-23T19:08:10.643487Z'} -
New CVE Received by [email protected]
Jul. 22, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'traefik', 'product': 'traefik', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '2.11.52', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '2.11.52', 'versionType': 'semver'}], 'packageURL': 'pkg:golang/Traefik', 'defaultStatus': 'unaffected'}, {'vendor': 'traefik', 'product': 'traefik', 'versions': [{'status': 'affected', 'version': '3.6.0', 'lessThan': '3.6.23', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '3.6.23', 'versionType': 'semver'}], 'packageURL': 'pkg:golang/Traefik', 'defaultStatus': 'unaffected'}, {'vendor': 'traefik', 'product': 'traefik', 'versions': [{'status': 'affected', 'version': '3.7.0', 'lessThan': '3.7.7', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '3.7.7', 'versionType': 'semver'}], 'packageURL': 'pkg:golang/Traefik', 'defaultStatus': 'unaffected'}] Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/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-22 Added Reference https://github.com/traefik/traefik/security/advisories/GHSA-cxjq-mrr5-89rv Added Reference https://www.vulncheck.com/advisories/traefik-before-authentication-bypass-via-replacepathregex