mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the mailcow web interface passes the raw `$_SERVER['REQUEST_URI']` to Twig as a global template variable and renders it inside a JavaScript string literal in the `setLang()` helper of `base.twig`, relying on Twig's default HTML auto-escaping instead of the context-appropriate `js` escaping strategy. In addition, the `query_string()` Twig helper merges all current `$_GET` parameters into the language-switching links on the login page, so attacker-supplied parameters are reflected and preserved across navigation. Version 2026-03b fixes the vulnerability.
History

Wed, 22 Apr 2026 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 22 Apr 2026 04:30:00 +0000

Type Values Removed Values Added
First Time appeared Mailcow
Mailcow mailcow Dockerized
Vendors & Products Mailcow
Mailcow mailcow Dockerized

Wed, 22 Apr 2026 00:00:00 +0000

Type Values Removed Values Added
Description mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the mailcow web interface passes the raw `$_SERVER['REQUEST_URI']` to Twig as a global template variable and renders it inside a JavaScript string literal in the `setLang()` helper of `base.twig`, relying on Twig's default HTML auto-escaping instead of the context-appropriate `js` escaping strategy. In addition, the `query_string()` Twig helper merges all current `$_GET` parameters into the language-switching links on the login page, so attacker-supplied parameters are reflected and preserved across navigation. Version 2026-03b fixes the vulnerability.
Title mailcow-dockerized Login Page has Reflected Parameter Injection / Wrong-Context XSS Escaping
Weaknesses CWE-79
References
Metrics cvssV4_0

{'score': 2.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-22T13:39:34.206Z

Reserved: 2026-04-15T15:57:41.719Z

Link: CVE-2026-40878

cve-icon Vulnrichment

Updated: 2026-04-22T13:39:26.423Z

cve-icon NVD

Status : Received

Published: 2026-04-21T20:17:01.403

Modified: 2026-04-21T20:17:01.403

Link: CVE-2026-40878

cve-icon Redhat

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