The Blocksy Companion plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.1.46 via the save_attachments function. This is due to the Custom Fonts extension registering a wp_check_filetype_and_ext filter that approves any filename containing .woff2 or .ttf as a substring via strpos() rather than validating that those strings appear as the final extension via PATHINFO_EXTENSION — allowing double-extension filenames such as shell.woff2.php to pass MIME validation and be handled as permitted font files. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible. This vulnerability is only exploitable when the premium version of the plugin (blocksy-companion-pro) is installed with both the WooCommerce Extra (Advanced Reviews) and Custom Fonts extensions active; the free blocksy-companion plugin does not contain the vulnerable code paths.

Blocksy Companion Pro plugin for WordPress before 2.1.47 contains an unauthenticated arbitrary file upload vulnerability that allows attackers to upload executable files by bypassing extension validation in the save_attachments function exposed through the Advanced Reviews feature. Attackers can exploit the Custom Fonts extension's flawed strpos() substring check by uploading double-extension filenames such as shell.woff2.php, causing the validation to pass on the substring match while the web server executes the file as PHP, achieving remote code execution.

The Blocksy Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via admin settings in all versions up to, and including, 2.1.45 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with editor-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.

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.

The Blocksy Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'blocksy_newsletter_subscribe' shortcode in all versions up to, and including, 2.1.14 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The Blocksy Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's blocksy_newsletter_subscribe shortcode in all versions up to, and including, 2.1.10 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The Freemius SDK, as used by hundreds of WordPress plugin and theme developers, was vulnerable to Cross-Site Request Forgery and Information disclosure due to missing capability checks and nonce protection on the _get_debug_log, _get_db_option, and the _set_db_option functions in versions up to, and including 2.4.2. Any WordPress plugin or theme running a version of Freemius less than 2.4.3 is vulnerable.

Server-Side Request Forgery (SSRF) vulnerability in Creative Themes Blocksy Companion blocksy-companion.This issue affects Blocksy Companion: from n/a through <= 2.0.42.

The Blocksy Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via SVG uploads in versions up to, and including, 2.0.45 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Cross-Site Request Forgery (CSRF) vulnerability in CreativeThemes Blocksy Companion.This issue affects Blocksy Companion: from n/a through 2.0.28.

The Blocksy Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's Newsletter widget in all versions up to, and including, 2.0.31 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The Blocksy Companion WordPress plugin before 1.8.82 does not ensure that posts to be accessed via a shortcode are already public and can be viewed, allowing any authenticated users, such as subscriber to access draft posts for example

Auth. (contributor+) Stored Cross-Site Scripting (XSS) vulnerability in CreativeThemes Blocksy Companion plugin <= 1.8.67 versions.