Hackers try to exploit WordPress plugin vulnerability that’s as severe as it gets

Hackers are assailing websites using a prominent WordPress plugin with millions of attempts to exploit a high-severity vulnerability that allows complete takeover, researchers said.

The vulnerability resides in WordPress Automatic, a plugin with more than 38,000 paying customers. Websites running the WordPress content management system use it to incorporate content from other sites. Researchers from security firm Patchstack disclosed last month that WP Automatic versions 3.92.0 and below had a vulnerability with a severity rating of 9.9 out of a possible 10. The plugin developer, ValvePress, silently published a patch, which is available in versions 3.92.1 and beyond.

Researchers have classified the flaw, tracked as CVE-2024-27956, as a SQL injection, a class of vulnerability that stems from a failure by a web application to query backend databases properly. SQL syntax uses apostrophes to indicate the beginning and end of a data string. By entering strings with specially positioned apostrophes into vulnerable website fields, attackers can execute code that performs various sensitive actions, including returning confidential data, giving administrative system privileges, or subverting how the web app works.

“This vulnerability is highly dangerous and expected to become mass exploited,” Patchstack researchers wrote on March 13.

Fellow web security firm WPScan said Thursday that it has logged more than 5.5 million attempts to exploit the vulnerability since the March 13 disclosure by Patchstack. The attempts, WPScan said, started slowly and peaked on March 31. The firm didn’t say how many of those attempts succeeded.

WPScan said that CVE-2024-27596 allows unauthenticated website visitors to create admin‑level user accounts, upload malicious files, and take full control of affected sites. The vulnerability, which resides in how the plugin handles user authentication, allows attackers to bypass the normal authentication process and inject SQL code that grants them elevated system privileges. From there, they can upload and execute malicious payloads that rename sensitive files to prevent the site owner or fellow hackers from controlling the hijacked site.

Successful attacks typically follow this process: