Understanding the Exploitation of CVE-2023-3460 in Ultimate Member Plugin


In a recent security incident, hackers have successfully exploited a zero-day vulnerability in the widely used Ultimate Member WordPress plugin. This critical flaw, known as CVE-2023-3460, allows attackers to bypass security measures and gain unauthorized access by creating rogue administrator accounts. With over 200,000 active installations, numerous websites are at risk of compromise. In this blog post, we will delve into the details of this vulnerability, its impact, and the necessary steps to protect your website.


Ultimate Member Plugin and Its Vulnerability

Ultimate Member is a popular WordPress plugin that empowers website administrators to create user profiles, build communities, and manage memberships seamlessly. Unfortunately, all versions of the plugin, including the latest version 2.6.6, are affected by the CVE-2023-3460 vulnerability. This privilege escalation flaw allows hackers to manipulate user meta values through the plugin's registration forms, specifically targeting the "wp_capabilities" meta value. By modifying this value, attackers can elevate their user role to that of an administrator, granting them complete control over the compromised website.


Exploitation and Indicators

Security experts at Wordfence were the first to discover attacks exploiting the CVE-2023-3460 vulnerability. Attackers take advantage of the plugin's flawed blocklist logic, allowing them to bypass key restrictions with ease. As a result, affected websites may experience various indicators of compromise, including the appearance of unauthorized administrator accounts, usernames such as "wpenginer," "wpadmins," "wpengine_backup," "se_brutal," and "segs_brutal," and records of malicious IP addresses accessing the Ultimate Member registration page. In some instances, attackers may even install malicious plugins and themes through the compromised site's administration panel.

The PoC for the vulnerability has not been released yet.

The Importance of Immediate Action

Given the critical nature of this vulnerability and the ongoing exploits, it is crucial for website owners to take immediate action to safeguard their websites. The developers of Ultimate Member have made efforts to address the flaw in recent versions, but the fixes have proven insufficient. Consequently, security experts strongly recommend uninstalling the Ultimate Member plugin until a comprehensive patch is released by the vendor. Even renowned security solutions like Wordfence cannot guarantee full protection against all exploitation scenarios, making removal the most prudent course of action.


Remediating the Risk

If your website has been compromised or you suspect it may have been, simply uninstalling the plugin will not be enough to mitigate the risk. It is essential to conduct a thorough malware scan to detect any remnants of the compromise, such as rogue administrator accounts and potential backdoors. Additionally, auditing all administrator-level users on your website is advised to identify any unauthorized accounts that may have been created by the attackers.



The exploitation of the CVE-2023-3460 vulnerability in the Ultimate Member WordPress plugin highlights the importance of staying vigilant and promptly addressing security vulnerabilities. Website administrators must prioritize the security of their sites by uninstalling the affected plugin and conducting comprehensive security measures. Regular updates, robust security practices, and proactive monitoring are key to safeguarding your website and protecting it from potential cyber threats.






Contributed by Dhabaleshwar Das

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