It was found that the fix for CVE-2014-0114 had been reverted in JBoss Operations Network 3 (JON). This flaw allows attackers to manipulate ClassLoader properties on a vulnerable server. Exploits that have been published rely on ClassLoader properties that are exposed such as those in JON 3. Additional information can be found in the Red Hat Knowledgebase article: https://access.redhat.com/site/solutions/869353. Note that while multiple products released patches for the original CVE-2014-0114 flaw, the reversion described by this CVE-2019-3834 flaw only occurred in JON 3.

Apache Commons BeanUtils, as distributed in lib/commons-beanutils-1.8.0.jar in Apache Struts 1.x through 1.3.10 and in other products requiring commons-beanutils through 1.9.2, does not suppress the class property, which allows remote attackers to "manipulate" the ClassLoader and execute arbitrary code via the class parameter, as demonstrated by the passing of this parameter to the getClass method of the ActionForm object in Struts 1.