What the vulnerability does
01Description
The Blocksy Companion plugin for WordPress is vulnerable to authenticated arbitrary file upload in all versions up to, and including, 2.1.19. This is due to insufficient file type validation detecting SVG files, allowing double extension files to bypass sanitization while being accepted as a valid SVG file. This makes it possible for authenticated attackers, with author level access and above, to upload arbitrary files on the affected site's server which may make remote code execution possible.
Explanation of Vulnerability in Simple Terms
02Summary
Blocksy Companion versions up to 2.1.19 allow authenticated users to upload files without proper validation. An attacker with low-level site access can upload malicious files, potentially gaining control of the site. Update to a version newer than 2.1.19 to fix this vulnerability.
What an attacker can do
03Attacker Capabilities
Upload malicious files to the site and execute code on the server.
Potential impact on your site
04Site Impact
Compromised site with potential data theft, malware injection, or complete takeover by an authenticated attacker.
Conditions required to exploit
05Prerequisites
Attacker needs a low-privilege user account (e.g., contributor or subscriber role).
Key dates
06Disclosure timeline
November 11, 2025
CVE published
April 8, 2026
Record updated
