Description
Grav is a file-based Web platform. Prior to 3.8.5, the Login plugin twofa_cancel task accepts a client-controlled _redirect field without a nonce and allows an unauthenticated request to set an external http, https, or protocol-relative Location target. Controller::execute() applies the field when taskTwofa_cancel() sets no redirect, and Grav::getRedirectResponse() accepts the target through Uri::isExternal(), enabling phishing redirects from a trusted Grav host. This issue is fixed in version 3.8.5.
References4
Metrics
- CVSS 4.0
-
5.3
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/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 - EPSS — exploit probability
- 1% percentile: 45 · as of 10 November 2026
- CWE
- CWE-601
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.