A critical vulnerability addressed in the Elementor WordPress plugin could allow authenticated users to upload arbitrary files to affected websites, potentially leading to code execution.
Elementor is a drag-and-drop website builder for WordPress that has more than 5 million installations.
Considered critical, the newly addressed vulnerability was apparently introduced on March 22, in version 3.6.0 of the plugin. Roughly one-third of websites were running a vulnerable version when the bug was found.
Researchers with Plugin Vulnerabilities, who identified the flaw, say that the issue exists because some functionalities did not perform capability checks, thus becoming available to users who shouldn’t have had access to them.
[ READ: Critical Flaw Impacts WordPress Plugin With 1 Million Installations ]
Due to the vulnerability, any authenticated user, regardless of their authorization, could make changes to the site, including by uploading arbitrary files.
Thus, the security hole could be exploited to achieve code execution and potentially completely take over the vulnerable site.
According to Patchstack researchers, the flaw resides in an “onboarding” module loaded on every request, and which was found hooked into the admin_init WordPress hook.
“This hook is fired on any admin-related screen/script but does not necessarily imply that it’s only fired when a higher privileged user is logged in on the site,” WordPress security company Patchstack explains.
The faulty module executes a POST payload action after checking if it has been sent along with a valid nonce, but, because the nonce token is sent to any authenticated user, it allows anyone to perform actions, regardless of their authorization.
The issue was addressed with the release of Elementor version 3.6.3. WordPress admins are advised to update to a patched version of the plugin as soon as possible.
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