Some serious security vulnerabilities existed in the Ninja Forms WordPress plugin that risked over a million sites. Exploiting these vulnerabilities could allow an attacker to takeover target websites and redirect incoming traffic to malicious links.
Ninja Forms Plugin Vulnerabilities
Team Wordfence has shared insights about vulnerabilities affecting another WordPress plugin Ninja Forms.
As revealed through their recent blog post, the researchers found 4 different vulnerabilities in the plugin.
One of these vulnerabilities included a critical severity bug that received a CVSS score of 9.9. Exploiting this flaw could lead to remote code execution and site takeover.
The other bug that exposed the OAuth connection key received a high-severity rating with a CVSS score of 7.7.
Whereas, the other two bugs received medium-severity ratings with CVSS scores of 4.8 (an open redirect vulnerability, and 6.1 (CSRF bug).
Regarding how the bugs could have affected a website when exploited, Wordfence stated,
One of these flaws made it possible for attackers to redirect site administrators to arbitrary locations.
The second flaw made it possible for attackers with subscriber level access or above to install a plugin that could be used to intercept all mail traffic.
The third flaw made it possible for attackers with subscriber level access to retrieve the Ninja Form OAuth Connection Key that could be used to establish a connection with the Ninja Forms central management dashboard.
The final flaw made it possible for attackers to disconnect a site’s OAuth Connection if they could trick a site’s administrator into performing an action.
Patches Rolled Out
Wordfence reported the vulnerabilities to the plugin developers on January 20, 2021. Following their report, the developers rolled out the fixes with the release of plugin version 3.4.34.
However, they missed deploying the fix for one of the bugs that the researchers pointed out again.
Eventually, another update rolled out 220.127.116.11 that addresses all the bugs.
Hence, all Ninja Forms plugin users should now ensure that their websites are running with the plugin version 18.104.22.168 or above. The most recent plugin version is 3.5.1.