CVE-2026-92553: YaySMTP arbitrary file upload vulnerability

high 8.8 published 2026-10-16

Affected versions: 2.7.7 and older
Fixed in: 2.7.8 *
Latest version: 2.7.9
Severity: High · CVSS 8.8
Active installs: 10,000+
Type: Arbitrary file upload

* The source does not name a fixed version; this is the first wordpress.org release after the last affected version.

What an attacker needs

Access: A logged-in account with Subscriber-level access or higher.

CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

What to do now

Update YaySMTP to 2.7.8 or newer (the latest is 2.7.9): Dashboard → Updates, or Plugins → “update now”.
If you cannot update right away, deactivate it until you can.
Turn on auto-updates for it: Plugins → “Enable auto-updates” on its row.
Not sure which version you run? Check your version against every known YaySMTP issue. With WP-CLI: wp plugin get yaysmtp --field=version.
If you ran an affected version and something looks off (new admin users, spam pages, redirects), run the free scan below.

The advisory

The YaySMTP – WP Mail SMTP with Email Logs, Tracking & Reports plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.7.7 via the putFile function. This is due to insufficient file type validation in the putFile function, as sanitize_file_name() does not strip executable extensions and no allow-list, MIME check, or safe-extension rename is applied. This makes it possible for authenticated attackers, with subscriber-level access and above, to upload files that may be executable, which makes remote code execution possible. The only server-side guard is a .htaccess file containing 'Require all denied' written by writeGuards(), which is silently ignored by nginx and by Apache configured with AllowOverride None, meaning RCE is fully achievable on those server configurations.

Description from the CVE record, published by Wordfence (the CVE Numbering Authority), via the NVD entry for CVE-2026-92553.

References

NVD CVE-2026-92553 nvd.nist.gov
Wordfence advisory www.wordfence.com
Code change (fix) plugins.trac.wordpress.org
Plugin source plugins.trac.wordpress.org

Ran an affected version? Check your site for signs of a hack

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Where this data comes from

CVE record, score and references: NIST National Vulnerability Database (NVD), checked 2026-11-04. This product uses data from the NVD API but is not endorsed or certified by the NVD.
Versions and install counts: wordpress.org/plugins/yaysmtp (Plugins API), fetched 2026-11-04.
The summary, “what an attacker needs” and “what to do” sections are our plain-English reading of the record and the plugin's release history; the quoted description is the record's own text. Spot an error? Email Daniel.