CVE-2026-40878

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-xv9r-j862-5hqf

Configurations

No configuration.

History

21 Apr 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-21 20:17

Updated : 2026-04-22 21:02

NVD link : CVE-2026-40878

Mitre link : CVE-2026-40878

CVE.ORG link : CVE-2026-40878

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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