CVE-2026-111255: affiliate-toolkit arbitrary file upload vulnerability
high 7.5 published 2026-10-28
- Affected versions
- 3.9.2 and older
- Fixed in
- 3.9.3 *
- Latest version
- 3.9.3
- Severity
- High · CVSS 7.5
- Active installs
- 2,000+
- 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 Contributor-level access or higher.
CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
What to do now
- Update affiliate-toolkit to 3.9.3 or newer: 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 affiliate-toolkit issue.
With WP-CLI:
wp plugin get affiliate-toolkit-starter --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 affiliate-toolkit – Multi-Network Affiliate & Amazon Product Display plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 3.9.2 via the upload_image function. This is due to insufficient file type validation in upload_image due to a weak Content-Type prefix check and extension derivation from the attacker-controlled URL path, with no dangerous-extension stripping. This makes it possible for authenticated attackers, with contributor-level access and above, to upload files that may be executable, which makes remote code execution possible. Exploitation requires the "import product image" option to be enabled in the plugin settings, as this activates the image download pipeline triggered on product post save.
References
- NVD CVE-2026-111255 nvd.nist.gov
- Wordfence advisory www.wordfence.com
- Code change (fix) plugins.trac.wordpress.org
- Plugin source plugins.trac.wordpress.org
Related
Ran an affected version? Check your site for signs of a hack
The free scan reads the public side of your site and looks for spam pages, hidden redirects, injected scripts and blacklist entries. No login, no install, about a minute.
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/affiliate-toolkit-starter (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.