A critical vulnerability in Apache Struts has been publicly disclosed in a security advisory. Talos has observed exploitation activity targeting CVE-2017-9805 in the wild. The vulnerability is similar to a zero-day vulnerability that was exploited back in March 2017. The latest in a long line of vulnerabilities that are exposing servers to potential exploitation. If you have a potentially vulnerable version of Apache struts there are two options: upgrade to Struts 2.5.13 or remove the REST plugin if it’s not actively being used.”]
Source: https://blog.talosintelligence.com/2017/09/apache-struts-being-exploited.html