BaselineWatch
Desk

CVE-2026-40875

7.0 high SSVC exploitation: poc Deferred

mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the user dashboard's "Seen successful connections" (login history) renders the client IP from login logs without HTML escaping. Because the server trusts the X-Real-IP header as the source IP for logging, an attacker can inject HTML/JS into this field. This Self-XSS can be exploited by a Login CSRF to force the victim into the attacker's account, and then read emails in a previous browser tab. Version 2026-03b fixes the vulnerability.

Fix

Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.

Change history 1

  1. First seenCVSS 7.0NVD modified 2026-10-26 21:10

Affected (CPE criteria) 0

NVD has not attached CPE configurations yet.

References 2