Vulnerability Description
The Swiss Toolkit For WP plugin for WordPress is vulnerable to arbitrary file upload due to a flawed file type validation bypass in the `upload_extension_files()` function in all versions up to, and including, 1.4.6. The `upload_extension_files()` function hooks into WordPress's `wp_check_filetype_and_ext` filter and uses `strpos()` to check if a filename contains a configured extension string, rather than verifying the actual file extension. This makes it possible for authenticated attackers, with Author-level access and above, to upload arbitrary files (including PHP) on the affected site's server which may make remote code execution possible, granted the "Enhanced Multi-Format Image Support" feature is enabled with at least one extension (e.g., avif) in the allowed formats.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://plugins.trac.wordpress.org/browser/swiss-toolkit-for-wp/tags/1.4.2/inclu
- https://plugins.trac.wordpress.org/browser/swiss-toolkit-for-wp/tags/1.4.2/inclu
- https://plugins.trac.wordpress.org/browser/swiss-toolkit-for-wp/trunk/includes/p
- https://plugins.trac.wordpress.org/browser/swiss-toolkit-for-wp/trunk/includes/p
- https://www.wordfence.com/threat-intel/vulnerabilities/id/06bccd2e-6891-433a-9f5
FAQ
What is CVE-2026-2354?
CVE-2026-2354 is a vulnerability with a CVSS score of 8.8 (HIGH). The Swiss Toolkit For WP plugin for WordPress is vulnerable to arbitrary file upload due to a flawed file type validation bypass in the `upload_extension_files()` function in all versions up to, and i...
How severe is CVE-2026-2354?
CVE-2026-2354 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-2354?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.