VulnerabilityDeferred

CVE-2026-40878

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.

LOW 2.1EPSS 0.80%

Does this matter?

Lower severity and a low EPSS score (0.80%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 4.0: 2.1 LOWCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.80% probability · 55th percentile
CISA KEV: Not listed
Weakness: CWE-79
Source: security-advisories@github.com

References

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

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.