CVE-2016-3081

Apache Struts is a web application framework. This flaw lets an outsider send a crafted web request that tricks the server into calling methods it shouldn’t—essentially allowing code to run on your server. Think of it like a receptionist that can be tricked into opening a door to an area it’s supposed to lock, without needing a key.

This matters if your business runs a website or web application built on Apache Struts (or software that embeds it). Your risk is specifically tied to running Apache Struts versions 2.3.19 through 2.3.28 with Dynamic Method Invocation enabled. It becomes a risk when the affected feature is enabled and the attacker can reach the web application over the network (no login is required).

This is urgent because it allows unauthenticated remote attackers to run arbitrary code, and an exploit module exists and is known to be weaponized. Even though there’s no KEV listing from CISA, the vulnerability’s exposure conditions (DMI enabled, network-reachable) make it a practical threat for exposed web apps, so you should address it now rather than later.