The Optimole – Optimize Images | Convert WebP & AVIF | CDN & Lazy Load | Image Optimization plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 's (missingsrcsets[][].s)' parameter in all versions up to, and including, 4.2.18 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The HMAC signature required to pass the REST endpoint's authorization check is published in plaintext to unauthenticated visitors inside the inline optimoleDataOptimizer JavaScript object on any page with an incomplete profile, making the effective authentication barrier nonexistent.

The Optimole – Optimize Images | Convert WebP & AVIF | CDN & Lazy Load | Image Optimization plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'comment' parameter in all versions up to, and including, 4.2.18 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Exploitation requires the comment to be approved by an administrator and for the affected post to contain at least one iframe or video element (e.g., a core Video block), which is sufficient under default plugin settings where video lazy loading is enabled.

The Optimole – Optimize Images | Convert WebP & AVIF | CDN & Lazy Load | Image Optimization plugin for WordPress is vulnerable to arbitrary file deletion due to insufficient file path validation in the replaceurlsinvalue function in all versions up to, and including, 4.2.19. This makes it possible for unauthenticated attackers to delete arbitrary files on the server, which can easily lead to remote code execution when the right file is deleted (such as wp-config.php). Successful exploitation requires PEAR's ArchiveTar library to be present and loadable on the host (common in official WordPress Docker images and many PHP distributions), and an administrator must subsequently use the plugin's Rename control on any attachment after the attacker has staged a malicious payload in a comment. Successful exploitation additionally requires an action by an administrator — the attacker cannot trigger the vulnerability on their own.