The Nextend Social Login and Register plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 3.1.21. This is due to missing or incorrect nonce validation on the 'unlinkUser' function. This makes it possible for unauthenticated attackers to unlink the user's social login via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

The Smart Slider 3 plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'data-href' parameter in all versions up to, and including, 3.5.1.38 due to insufficient input sanitization and output escaping. 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 Smart Slider 3 plugin for WordPress is vulnerable to unauthorized access and modification of data due to missing capability checks on multiple wpajaxsmart-slider3 controller actions in all versions up to, and including, 3.5.1.33. The displayadminajax() method does not call checkForCap() (which requires unfilteredhtml capability), and several controller actions only validate the nonce (validateToken()) without calling validatePermission(). This makes it possible for authenticated attackers, with Contributor-level access and above, to enumerate slider metadata and create, modify, and delete image storage records by obtaining the nextendnonce exposed on post editor pages.

Smart Slider 3 Pro version 3.5.1.35 for WordPress and Joomla contains a multi-stage remote access toolkit injected through a compromised update system that allows unauthenticated attackers to execute arbitrary code and commands. Attackers can trigger pre-authentication remote shell execution via HTTP headers, establish authenticated backdoors accepting arbitrary PHP code or OS commands, create hidden administrator accounts, exfiltrate credentials and access keys, and maintain persistence through multiple injection points including must-use plugins and core file modifications.

The Smart Slider 3 plugin for WordPress is vulnerable to Arbitrary File Read in all versions up to, and including, 3.5.1.33 via the 'actionExportAll' function. This makes it possible for authenticated attackers, with Subscriber-level access and above, to read the contents of arbitrary files on the server, which can contain sensitive information.

The Smart Slider 3 plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the upload function in all versions up to, and including, 3.5.1.22. This makes it possible for authenticated attackers, with contributor-level access and above, to upload files, including SVG files, which can be used to conduct stored cross-site scripting attacks.

The Nextend Social Login Pro plugin for WordPress is vulnerable to authentication bypass in versions up to, and including, 3.1.16. This is due to insufficient verification on the user being supplied during the Apple OAuth authenticate request through the plugin. This makes it possible for unauthenticated attackers to log in as any existing user on the site, such as an administrator, if they have access to the email.