A critical vulnerability affecting the Houzez premium WordPress theme has been exploited in the wild, WordPress security company Patchstack warned on Monday.

Houzez is a premium theme for the real estate industry, with more than 35,000 sales on ThemeForest. It allows agencies to easily manage content and listings.

Patchstack CTO Dave Jong discovered recently that the Houzez theme and its associated Houzez Login Register plugin are impacted by a critical vulnerability that can allow an unauthenticated attacker to hack WordPress websites.

“The theme itself provides registration functionality (must be turned on in the settings) which also allows the user to provide the user role they want to sign up with. Unfortunately, this could be set to administrator to instantly get administrator privileges on the WordPress site,” Jong explained in a blog post.  

The vulnerability is tracked as CVE-2023-26009 in the Houzez plugin and CVE-2023-26540 in the theme. The vendor was informed about the security hole and patched it with the release of versions 2.6.4 (plugin) and 2.7.2 (theme).

Patchstack has been seeing attempts to exploit the vulnerability in the wild, and Jong told SecurityWeek that both the theme and the plugin have been targeted. However, the plugin seems to be targeted more than the theme — it’s unclear why.

According to Jong, an attacker looking to exploit the vulnerability needs to visit the targeted website, grab a nonce token associated with CSRF protection, and then send a maliciously crafted request to the account registration endpoint provided by the Houzez theme or plugin.

Patchstack could not determine what the attackers are hoping to achieve by hacking websites through the Houzez vulnerability because its products block the exploitation attempts.

“However, it is safe to assume that if a site is exploited with this vulnerability and the attacker is logged in with administrator privileges, they are likely to upload a malicious plugin which contains a backdoor,” Jong explained. “This backdoor may perform actions such as listening for commands to be executed on a future date, inject advertisements into the website or redirect traffic to another malicious site.”

The expert added, “These kinds of vulnerabilities tend to be exploited the most as it requires no authentication and it instantly gives the malicious actor access to an account with administrator privileges. Vulnerabilities that require multiple steps or a much higher initial privilege do not tend to be exploited very often as the success rate tends to be lower and it requires much more time and processing power on top of the fact that they don’t tend to give the malicious actor access to write files onto the filesystem of the website.”

WordPress website owners and administrators using the Houzez theme should ensure that their installation is patched to prevent malicious exploitation. 

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