CVE-2026-40878: mailcow-dockerized Login Page has Reflected Parameter Injection / Wrong-Context XSS Escaping
mailcow · mailcow-dockerized
Affected: mailcow-dockerized · Exploitation: check available, not yet exploited
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 57% of scored CVEs
DescriptionCVE.org
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.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- mailcow · mailcow-dockerized< 2026-03b
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Check available, not yet exploited. A public nuclei template can confirm it on a system you are authorised to test.
- CISA KEV
- Not listed
- Public check
- Mailcow < 2026-03b - Href Link Injection · nuclei template in projectdiscovery/nuclei-templates
- Weakness
- Cross-site Scripting
- Vendor
- mailcow
- Published
- April 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-40878 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.