According to cyber security researchers, there is a critical security flaw in the LiteSpeed Cache plugin for WordPress that users can exploit without authentication to gain administrative privileges on the site. It is an all-in-one site acceleration plugin that features an exclusive server-level cache along with a suite of optimization features designed to make the websites more efficient with LiteSpeed Cache for WordPress. As a WordPress Multisite plugin, LowSide supports a wide range of plugins, including WooCommerce, bbPress, and Yoast SEO, for the best possible experience. 

There is no compatibility issue with ClassicPress when using LiteSpeed Cache for WordPress. In LiteSpeed Cache, which comes bundled with WordPress, there is a critical vulnerability that can allow attackers to take full control of millions of sites once a rogue admin account is created. This is an open-source and almost universally popular WordPress site acceleration plugin with over 5 million active installations, and it also supports WooCommerce, bbPress, ClassicPress, and Yoast SEO. It is available as a free download. 

In LiteSpeed Cache versions 6.3.0.1 and earlier, the plugin's user simulation feature has an unauthenticated privilege escalation vulnerability (CVE-2024-28000). As a result of this vulnerability, the highest bounty has been awarded in the history of bug bounty hunting for WordPress. This researcher has been rewarded USD 14,400 in cash through the Patchstack Zero Day program as part of this award. It would be great if anyone else interested in joining the community as well would be able to benefit from the program. 

This vulnerability has been automatically protected for all Patchstack users who have enabled protection, so they are no longer at risk. For only $5 per site per month, Patchstack offers a free Community account, where users can scan for vulnerabilities and apply protection for only $5 / site per month by creating a PatchStack account. It is the plugin's user simulation feature that is vulnerable to the vulnerability, as it uses a weak security hash as part of its security process. 

It must be said that the hash value is generated by using an insecure random number generator and the value is stored without being salted or related to a particular request made by the user.  The Patchstack security research tool warns that the hash is relatively easy to guess due to the limited number of possible values, which allows attackers to iterate through all possible hashes to discover the appropriate one and to simulate a user who is an administrator. 

This vulnerability affects all versions of the LiteSpeed Cache plugin for WordPress, from version 6.3.0.1 onwards. In addition, the plugin is susceptible to privilege escalation attacks. Certainly! Here is the rewritten information in a formal, expanded, and third-person tone: --- The security vulnerability identified as CVE-2024-28000 in the LiteSpeed Cache plugin has been linked to a critical issue concerning the improper restriction of role simulation functionality. This flaw allows a user with access to a valid hash—discoverable through debug logs or susceptible to brute-force attacks—to alter their current user ID to that of an administrator. 

This, in turn, enables unauthenticated attackers to impersonate an administrator and utilize the `/wp-json/wp/v2/users` REST API endpoint to create a new user account with administrative privileges. The vulnerability is present in all versions of the LiteSpeed Cache plugin up to and including version 6.3.0.1. The vulnerability was addressed in LiteSpeed Cache version 6.4, released on August 13, 2024. Website administrators utilizing the plugin are strongly advised to update to this latest version to prevent exploitation. 

The urgency of this update is underscored by a report from Wordfence, a leading WordPress security provider, which disclosed that over 30,000 attacks targeting CVE-2024-28000 were blocked within a single day. This surge in attacks illustrates the swift adoption of this exploit by cybercriminals, who are leveraging the vulnerability to compromise WordPress installations. Currently, the attacks are predominantly directed at non-Windows-based WordPress sites. This is because the vulnerability exploits a PHP method called `sys_getloadavg()`, which is not available on Windows systems. 

Consequently, while Windows-based WordPress installations are not vulnerable to this specific exploit, other systems remain at significant risk. The flaw was reported to Patchstack's bug bounty program by security researcher John Blackbourn on August 1, 2024. The LiteSpeed development team promptly created and released a patch with LiteSpeed Cache version 6.4 on August 13. Successful exploitation of this vulnerability can grant unauthenticated visitors administrator-level access, potentially allowing them to fully control compromised websites. 

This control includes installing malicious plugins, altering critical settings, redirecting traffic to harmful sites, distributing malware to visitors, or stealing user data. Additionally, in June 2024, the Wordfence Threat Intelligence team reported that a threat actor had compromised at least five plugins on WordPress.org, adding malicious PHP scripts to enable the creation of administrator accounts on affected websites. 

To protect against this vulnerability, Wordfence Premium, Wordfence Care, and Wordfence Response users were provided with a firewall rule effective from August 20, 2024. Users of the free version of Wordfence will receive similar protection starting on September 19, 2024.