🛡️ CVE-2026-40873
Description
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.
Weakness class
CVE-2026-40873 is classified as CWE-79: Cross-site Scripting (XSS). User-supplied data is written into a page without escaping, so attacker script runs in the browser of anyone who views it.
Affected software
CVE-2026-40873 is recorded against 1 package.
- unknown
Timeline and source
Published on 21 April 2026 and last revised on 17 June 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.
References
Details
Affected Packages
| Software | From version | Fixed in |
|---|---|---|
| unknown | — | — |
References
Similar Threats
- Unknown CVE-2022-0003
- Unknown CVE-2022-0303
- High CVE-2022-1206
- Unknown CVE-2022-0931
- Unknown CVE-2022-0094
More CVE 2026 advisories
Browse all of CVE 2026 in the advisory index.
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