Malware that exploits unpatched vulnerabilities in 30 different WordPress plugins has infected hundreds if not thousands of sites and may have been in active use for years, according to a writeup published last week.
The Linux-based malware installs a backdoor that causes infected sites to redirect visitors to malicious sites, researchers from security firm Dr.Web said. It’s also able to disable event logging, go into standby mode, and shut itself down. It gets installed by exploiting already-patched vulnerabilities in plugins that website owners use to add functionality like live chat or metrics-reporting to the core WordPress content management system.
“If sites use outdated versions of such add-ons, lacking crucial fixes, the targeted web pages are injected with malicious JavaScripts,” Dr.Web researchers wrote. “As a result, when users click on any area of an attacked page, they are redirected to other sites.”