A popular plugin for the WordPress website builder (opens in new tab) with more than two million active installs carried a severe flaw which allowed threat actors to steal sensitive data from visitors and, in some cases, take over the website, entirely.
The plugin is called Advanced Custom Fields which, together with its Pro version, gives website administrators more control over the website’s content and data.
However, the plugin was vulnerable to a cross-site scripting (XSS) attack, which allows attackers to inject malicious code into vulnerable websites. The code then gets run in the visitor’s browser, allowing the attackers to grab sensitive data. If one of the visitors also turns out to be the site’s admin, the attacker can grab their data too, and ultimately take over the website, completely.
Patching the flaw
The vulnerability was first discovered in May 2023 by Patchstack researcher Rafie Muhammad and reported to the plugin’s vendor, Delicious Brains.
It was given a tracking number of CVE-2023-30777, and was rated 6.1/10 in severity. Two months later, in early April, Delicious Brains issued a patch that addressed the flaw, which also brought the plugin up to version 6.1.6. Admins worried about cross-site scripting attacks should make sure their plugin is brought up to this version as soon as possible.
“This vulnerability allows any unauthenticated user [to steal] sensitive information to, in this case, privilege escalation on the WordPress site by tricking the privileged user to visit the crafted URL path,” Patchstack says. “This vulnerability could be triggered on a default installation or configuration of Advanced Custom Fields plugin. The XSS also could only be triggered from logged-in users that have access to the Advanced Custom Fields plugin,” the researchers concluded.
As per The Register, the flaw is relatively straightforward and is one of four found in this plugin in the last couple of years.
Via: The Register (opens in new tab)