Mailcow vulnerabilities
Published CVEs affecting Mailcow products: 7 record(s), with severity, exploitation and fixes.
CVE-2026-7460
High · 7.4
CWE-79 May 20, 2026
mailcow-dockerized 2026-03b - Stored XSS in Queue Manager via unescaped
mailcow-dockerized contains a stored cross-site scripting vulnerability in the administrator Queue Manager. The Queue Manager fetches mail queue entries from /api/v1/get/mailq/all, copies server-controlled Postfix queue fields into DataTables rows, and renders several of those fields as HTML without adequate output encoding.
This issue affects mailcow-dockerized: 2026-03b.
CVE-2026-40878
Low · 2.1
Public exploit CWE-79 Apr 21, 2026
mailcow-dockerized Login Page has Reflected Parameter Injection / Wrong-Context XSS Escaping
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.
CVE-2026-40875
High · 7.0
CWE-79 Apr 21, 2026
mailcow: dockerized vulnerable to stored XSS in user login history real_rip
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.
CVE-2026-40874
Medium · 6.0
CWE-284 Apr 21, 2026
mailcow: dockerized missing authorization on Forwarding Hosts delete action
mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, no administrator verification takes place when deleting Forwarding Hosts with `/api/v1/delete/fwdhost`. Any authenticated user can call this API. Checks are only applied for edit/add actions, but deletion can still significantly disrupt the mail service. Version 2026-03b fixes the vulnerability.
CVE-2026-40873
High · 8.9
CWE-79 Apr 21, 2026
mailcow: dockerized vulnerable to stored XSS in Quarantine attachment filenames
mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the Quarantine details modal injects attachment filenames into HTML without escaping, allowing arbitrary HTML/JS execution. An attacker can deliver an email with a crafted attachment name so that when an admin views the quarantine item, JavaScript executes in their browser, taking over their account. Version 2026-03b fixes the vulnerability.
CVE-2026-40872
Critical · 9.3
CWE-79 Apr 21, 2026
mailcow: dockerized - Stored XSS in Autodiscover Admin Logs
mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the admin dashboard's Autodiscover logs render the EMailAddress value (logged as the "user" field) without HTML escaping. By submitting an unauthenticated Autodiscover request with a crafted EMailAddress containing HTML/JS, the payload is stored in Redis and executed when an admin views the Autodiscover logs. Version 2026-03b fixes the vulnerability.
CVE-2026-40871
High · 7.2
CWE-20 Apr 21, 2026
mailcow: dockerized vulnerable to Second Order SQL Injection in quarantine category via API
mailcow: dockerized is an open source groupware/email suite based on docker. Versions prior to 2026-03b have a second-order SQL injection vulnerability in the quarantine_category field via the Mailcow API. The /api/v1/add/mailbox endpoint stores quarantine_category without validation or sanitization. This value is later used by quarantine_notify.py, which constructs SQL queries using unsafe % string formatting instead of parameterized queries. This results in a delayed (second-order) SQL injection when the quarantine notification job executes, allowing an attacker to inject arbitrary SQL. Using a UNION SELECT, sensitive data (e.g., admin credentials) can be exfiltrated and rendered inside quarantine notification emails. Version 2026-03b fixes the vulnerability.