CVE-2026-40910: frp is a fast reverse proxy. From 0.43.0 to 0.68.0, frp contains an authentication bypass in the HTTP vhost routing path when routeByHTTPUser is used as part…

PriorityP260critical9.1CVSS 3.1

AVNACLPRNUINSUCHIHAN

EPSS

0.27%

18.4th percentile

frp is a fast reverse proxy. From 0.43.0 to 0.68.0, frp contains an authentication bypass in the HTTP vhost routing path when routeByHTTPUser is used as part of access control. In proxy-style requests, the routing logic uses the username from Proxy-Authorization to select the routeByHTTPUser backend, while the access control check uses credentials from the regular Authorization header. As a result, an attacker who can reach the HTTP vhost entrypoint and knows or can guess the protected routeByHTTPUser value may access a backend protected by httpUser / httpPassword even with an incorrect Proxy-Authorization password. This issue affects deployments that explicitly use routeByHTTPUser. It does not affect ordinary HTTP proxies that do not use this feature. This vulnerability is fixed in 0.68.1.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
fatedier	frp	< 0.68.1	0.68.1
fatedier	frp	>= 0.43.0 < 0.68.1	0.68.1

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