CVE-2026-40910: CWE-287: Improper Authentication in fatedier frp
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.
AI Analysis
Technical Summary
CVE-2026-40910 is an improper authentication vulnerability (CWE-287) in fatedier frp, a fast reverse proxy. Between versions 0.43.0 and 0.68.0, when routeByHTTPUser is enabled, the HTTP vhost routing path uses the username from the Proxy-Authorization header to select the backend, but validates access control using the Authorization header. This mismatch allows an attacker who can reach the HTTP vhost entrypoint and knows or guesses the routeByHTTPUser value to access protected backends despite incorrect Proxy-Authorization credentials. The vulnerability does not affect ordinary HTTP proxies that do not use routeByHTTPUser. The issue is resolved in version 0.68.1.
Potential Impact
Successful exploitation allows an attacker to bypass authentication controls on backends protected by httpUser/httpPassword when using routeByHTTPUser, potentially leading to unauthorized access to sensitive backend services. The CVSS 3.1 base score is 6.5 (medium severity), reflecting high confidentiality impact but low integrity and no availability impact. There are no known exploits in the wild as of the published date.
Mitigation Recommendations
This vulnerability is fixed in frp version 0.68.1. Users should upgrade to version 0.68.1 or later to remediate the issue. Since no official patch link or advisory is provided, verify the upgrade availability from the vendor's official sources. Deployments not using routeByHTTPUser are not affected. Patch status is not yet confirmed via vendor advisory; check the vendor's official channels for current remediation guidance.
CVE-2026-40910: CWE-287: Improper Authentication in fatedier frp
Description
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-40910 is an improper authentication vulnerability (CWE-287) in fatedier frp, a fast reverse proxy. Between versions 0.43.0 and 0.68.0, when routeByHTTPUser is enabled, the HTTP vhost routing path uses the username from the Proxy-Authorization header to select the backend, but validates access control using the Authorization header. This mismatch allows an attacker who can reach the HTTP vhost entrypoint and knows or guesses the routeByHTTPUser value to access protected backends despite incorrect Proxy-Authorization credentials. The vulnerability does not affect ordinary HTTP proxies that do not use routeByHTTPUser. The issue is resolved in version 0.68.1.
Potential Impact
Successful exploitation allows an attacker to bypass authentication controls on backends protected by httpUser/httpPassword when using routeByHTTPUser, potentially leading to unauthorized access to sensitive backend services. The CVSS 3.1 base score is 6.5 (medium severity), reflecting high confidentiality impact but low integrity and no availability impact. There are no known exploits in the wild as of the published date.
Mitigation Recommendations
This vulnerability is fixed in frp version 0.68.1. Users should upgrade to version 0.68.1 or later to remediate the issue. Since no official patch link or advisory is provided, verify the upgrade availability from the vendor's official sources. Deployments not using routeByHTTPUser are not affected. Patch status is not yet confirmed via vendor advisory; check the vendor's official channels for current remediation guidance.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-15T16:37:22.767Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e7e20f19fe3cd2cdf8e2a1
Added to database: 4/21/2026, 8:46:07 PM
Last enriched: 4/21/2026, 9:01:14 PM
Last updated: 4/22/2026, 6:06:01 AM
Views: 9
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