CVE-2026-40910
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk19th percentile - higher than 19% of all known CVEs
Summary
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, routing uses the username from Proxy-Authorization to select the routeByHTTPUser backend, while the access control check uses credentials from the regular Authorization header, allowing an attacker to access a backend protected by httpUser/httpPassword even with an incorrect Proxy-Authorization password. This is fixed in 0.68.1.
Risk Assessment
An attacker who knows or can guess the routeByHTTPUser value may access a backend protected by httpUser/httpPassword without valid credentials. This affects only deployments that explicitly use routeByHTTPUser.
Recommendation
Upgrade frp to version 0.68.1 or later. If routeByHTTPUser is not needed, disable it and verify the access control configuration.
Other vulnerabilities in frp
See all- CVE-2026-110619Medium
frp 0.41.0 through 0.71.1 contains a missing authentication vulnerability that allows unauthenticated remote attackers to access pprof debug endpoints because handlers are registered on the root mux outside Basic Authentication. Attackers can query /debug/pprof/ endpoints on frps dashboard or frpc admin listeners to obtain cmdline, goroutine stacks, heap profiles, and trigger CPU profiling.
- CVE-2026-73564High
frp versions 0.53.0 through 0.70.1 have a vulnerability in the optional SSH Tunnel Gateway in pkg/ssh/server.go, where parsing an SSH exec channel request adds 4 to an attacker-controlled length. A length of 0xFFFFFFFF makes the uint32 addition wrap to 3, defeating the bounds check and causing a panic in TunnelServer.handleNewChannel. When no authorized-keys file is configured, an unauthenticated peer can reach this phase before the frp token is checked, and a single five-byte request terminates the frps process and drops every active tunnel. The issue is fixed in version 0.70.1.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS