Sent from one of many spoofed addresses used to trick victims into believing that the sender really is Adobe (email@example.com, firstname.lastname@example.org, etc.), the message is usually a variation on "Thank you for buying [random Adobe software]. Your Adobe License key is in attached document below."
The attached ZIP file (License_Key_[random 6-digit alphanumeric combination].zip) contains the 209 kB large License_Key_Document_Adobe_Systems_Incorporated.exe file, which is currently detected as malicious by 17 of the 49 AV solutions used by VirusTotal.
It's a Trojan capable of downloading additional malicious files from the Internet, and attempts to prevent researchers from analysing it and users from spotting it by trying to detect the use of a virtual machine and known forensic tools, and terminate AV products.
As always, users are advised to be wary of unsolicited emails, and never to blindly follow links and download files included in them.