An estimated 16,000 WordPress websites are running a plugin that is vulnerable to unauthenticated plugin option updates.
WordFence, a WordPress security solution provider, has reported that the plugin Rich Reviews has a vulnerability that is currently being abused and can be exploited to deliver stored cross-site scripting (XSS) payloads. This can result in malvertisements being injected, causing pop up ads and redirects to appear on the site using the plugin.
“The Wordfence team is seeing this in our attack data and our Security Services Team has assisted customers of our site cleaning service who have had their site compromised by an attacker who exploited this vulnerability,” the firm stated.
Tripwire reported the pop ups lead people to webpages containing porn, scams, and additional malware designed to infect users’ computers.
The plugin’s developer was contacted by WordFence about the problem and responded that it is working on a fix, but there is no timeline for when it might be available.
UPDATE: Magic Box Software contacted SC Media with word that it had created a modified version of Nuanced Media’s Rich Reviews plugin that is hardened to avoid the XSS exploit going around.
Complicating matters is the fact that Rich Reviews was removed from the WordPress plugin repository six months ago. So even if a patch is developed there no avenue for it to be distributed to users.
Because of this situation WordFence is recommending the plugin users find another solution and remove Rich Reviews from their sites.
WordPress plugins are a frequent target for hackers, with many issues reported this year.