frp has an authentication bypass in HTTP vhost routing when routeByHTTPUser is used for access control

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N

EPSS

• CVE-2026-40910: 0.27% estimated exploitation activity in the next 30 days; percentile 19.12 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary 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. Details The issue is in pkg/util/vhost/http.go. In proxy-style requests using an absolute URI, the routing path extracts the username from Proxy-Authorization and stores it as the request HTTPUser, which is then used for routeByHTTPUser route selection. More specifically,…

Published by the source

14 Apr 2026, 23:33 UTC

Last modified by the source

24 Apr 2026, 20:30 UTC

Source last checked

26 Oct 2026, 15:19 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-pq96-pwvg-vrr9

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# Patch Next advisory brief: CVE-2026-40910

Advisory: frp has an authentication bypass in HTTP vhost routing when routeByHTTPUser is used for access control
IDs: CVE-2026-40910, GHSA-pq96-pwvg-vrr9
Record: https://patchnext.com/advisories/cve-2026-40910 (revision 1, source checked 26 Oct 2026, 15:19 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/fatedier/frp 0.68.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/fatedier/frp: affected >= 0.43.0, <= 0.68.0; fixed in 0.68.1

## Suggested inspection (read-only)
- Go github.com/fatedier/frp: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/fatedier/frp.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-pq96-pwvg-vrr9 (GitHub-reviewed advisory GHSA-pq96-pwvg-vrr9 lists affected ranges: Go github.com/fatedier/frp >=0.43.0 <=0.68.0)

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