Is Autoptimize safe? Known vulnerabilities and latest version

The Autoptimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Author Name in all versions up to, and including, 3.1.15.1 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 an administrator to have enabled Autoptimize's 'Lazy-load images?' option, the w3-total-cache/w3-total-cache.php file to be present on disk with the plugin disabled, a class named Minify_HTML to be loaded into scope by another plugin, and the malicious comment to be approved by a moderator before the payload renders.

The Autoptimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via REQUEST_URI Path in all versions up to, and including, 3.1.15.1 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 Critical CSS feature to be active with a valid API key configured, as this is the precondition for unauthenticated frontend requests to trigger queue entries via ao_ccss_enqueue().

The Autoptimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the lazy-loading image processing in all versions up to, and including, 3.1.14. This is due to the use of an overly permissive regular expression in the `add_lazyload` function that replaces all occurrences of `\ssrc=` in image tags without limiting to the actual attribute. 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 by crafting an image tag where the `src` URL contains a space followed by `src=`, causing the regex to break the HTML structure and promote text inside attribute values into executable HTML attributes.

The Autoptimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'ao_post_preload' meta value in all versions up to, and including, 3.1.14. This is due to insufficient input sanitization in the `ao_metabox_save()` function and missing output escaping when the value is rendered into a `<link>` tag in `autoptimizeImages.php`. 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, granted the "Image optimization" or "Lazy-load images" setting is enabled in the plugin configuration.

The Autoptimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the LCP Image to preload metabox in all versions up to, and including, 3.1.13 due to insufficient input sanitization and output escaping on user-supplied image attributes in the "create_img_preload_tag" function. 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 Autoptimize WordPress plugin before 3.1.7 does not sanitise and escape the settings imported from a previous export, allowing high privileged users (such as an administrator) to inject arbitrary javascript into the admin panel, even when the unfiltered_html capability is disabled, such as in a multisite setup.

The Autoptimize WordPress plugin before 3.1.0 uses an easily guessable path to store plugin's exported settings and logs.

The Autoptimize WordPress plugin before 3.1.1 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup)

The Autoptimize WordPress plugin before 2.7.8 attempts to delete malicious files (such as .php) form the uploaded archive via the "Import Settings" feature, after its extraction. However, the extracted folders are not checked and it is possible to upload a zip which contained a directory with PHP file in it and then it is not removed from the disk. It is a bypass of CVE-2020-24948 which allows sending a PHP file via the "Import Settings" functionality to achieve Remote Code Execution.

The Autoptimize WordPress plugin before 2.7.8 attempts to remove potential malicious files from the extracted archive uploaded via the 'Import Settings' feature, however this is not sufficient to protect against RCE as a race condition can be achieved in between the moment the file is extracted on the disk but not yet removed. It is a bypass of CVE-2020-24948.

The Autoptimize WordPress plugin before 2.7.8 does not check for malicious files such as .html in the archive uploaded via the 'Import Settings' feature. As a result, it is possible for a high privilege user to upload a malicious file containing JavaScript code inside an archive which will execute when a victim visits index.html inside the plugin directory.

The Autoptimize WordPress plugin before 2.8.4 was missing proper escaping and sanitisation in some of its settings, allowing high privilege users to set XSS payloads in them, leading to stored Cross-Site Scripting issues