Skip to content ↓ | Skip to navigation ↓

Researchers have identified multiple privilege escalation and cross-site scripting vulnerabilities in the popular WordPress Plugin All in One SEO Pack, which is currently estimated to be running on more than 15 million of the 73 million WordPress websites.

“While auditing their code, we found two security flaws that allows an attacker to conduct privilege escalation and cross site scripting (XSS) attacks,” wrote Marc-Alexandre Montpas.

“In the first case, a logged-in user, without possessing any kind of administrative privileges (like an author of subscriber), could add or modify certain parameters used by the plugin. It includes the post’s SEO title, description and keyword meta tags. All of which could decrease one’s website’s Search Engine Results Page (SERP) ranking if used maliciously.”

Montpas went on to explain that his team also discovered that the vulnerability can be used in combination with another flaw which could allow an attacker to execute malicious Javascript on an unpatched website’s administrator control panel.

“This means that an attacker could potentially inject any javascript code and do things like changing the admin’s account password to leaving some backdoor in your website’s files in order to conduct even more ‘evil’ activities later,” Montpas said.

“If your site has subscribers, authors and non-admin users logging in to wp-admin, you are a risk. If you have open registration, you are at risk, so you have to update the plugin now… We’re not going to reinvent the wheel on this one: upgrade to the latest version available for this plugin.”