This indicates an attack attempt to exploit a Memory Corruption vulnerability in Adobe Acrobat and Reader.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted file. A remote attacker may be able to exploit this to execute arbitrary code within the context of the application, via a crafted file.
Adobe Flash Player Desktop Runtime 126.96.36.199 and earlier versions on Windows, Macintosh
Adobe Flash Player for Google Chrome 188.8.131.52 and earlier versions on Windows, Macintosh, Linux and Chrome OS
Adobe Flash Player for Microsoft Edge and Internet Explorer 11 184.108.40.206 and earlier versions on Windows 10 and 8.1
Adobe Flash Player Desktop Runtime 220.127.116.11 and earlier versions on Linux
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.