Vulnerabilities have been discovered in the popular All In One SEO Pack WordPress plugin that could allow privilege escalation and cross-site scripting attacks. The plugin has been patched and users should ensure that they immediately update to the most recent version or there is a real risk of their WordPress site being compromised.
In a recent post on the Sucuri Blog security researcher Marc-Alexandre Montpas revealed the discovery of a pair of critical vulnerabilities in the plugin, which is used for search engine optimization on a large number of WordPress sites. The free version of the All In One SEO plugin has over 18 million downloads and provides features like meta tag generation, XML sitemap support, and robots.txt control.
According to Montpas, two exploitable vulnerabilities were discovered. The first allows logged-in users without admin privileges — an author or ordinary user, for example – to adjust parameters used by the plugin to change title tags, meta description tags, and keyword meta tags. By changing these parameters, a malicious user could cause a site’s search engine optimization to be degraded — a serious problem for sites that depend on Google for referrals.