CVEvulnerability

CVE-2026-40875

7.0 HIGH Published 2026-04-21 Modified 2026-10-26 Official page ↗
Status
Deferred
Published
2026-04-21
Last modified
2026-10-26
Assigner
[email protected]
CVSS 4.0 ([email protected])
7.0 HIGH — CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:H/VI:N/VA:N/SC:H/SI:H/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
Weaknesses
CWE-79, CWE-80

Description

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.

Related

Weakness · CWE (2)

  • CWE-79 Improper Neutralization of Input During Web Page Generation weakness
  • CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page weakness

References