Description
Wallos is an open-source, self-hostable personal subscription tracker. Prior to version 5.0.0, Wallos lets any authenticated user store an arbitrary SMTP host — including private and cloud-metadata IP addresses — in their personal email notification settings, with no server-side SSRF validation. When the scheduled notification cron job runs, it passes the stored host directly to PHPMailer, causing the Wallos server to open an outbound TCP connection to whatever address the attacker specified. This gives a low-privileged attacker a reliable mechanism to probe internal network services from the server's perspective. This issue has been patched in version 5.0.0.
References3
Metrics
- CVSS 3.1
-
3.5
LOW
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 22 · as of 8 November 2026
- CWE
- CWE-918
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.