Description
Wallos is an open-source, self-hostable personal subscription tracker. Prior to version 4.9.4, login.php generates an OIDC state nonce stored in $_SESSION['oidc_state'], but checksession.php dispatches the OIDC callback without comparing the incoming state against the session value. An attacker can trick a victim into visiting a crafted URL, causing Wallos to exchange the attacker's authorization code and log the victim into the attacker's account. This issue has been patched in version 4.9.4.
References3
Metrics
- CVSS 4.0
-
7.5
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/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
- 0% percentile: 13 · as of 8 November 2026
- CWE
- CWE-352
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.