SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-2354

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.

HIGH 8.8EPSS 1.00%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.00%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
1.00% probability · 61th percentile
CISA KEV
Not listed
Weakness
CWE-434
Source
security@wordfence.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.