The Apache Struts 2 Vulnerability

Recently one of the largest credit management organizations in the US was compromised, with around 143 million accounts stolen. As has been reported, these accounts included personally identifiable information (PII) such as names, addresses, social security numbers, credit histories, and even credit card information.

https://blog.fortinet.com/2017/09/18/the-apache-struts-2-vulnerability-one-of-the-largest-data-breaches-in-history