Online users who have received unexpected email messages with attached files with names ending with .ace are asked not to open them. This is because the attachments are compressed malicious files that contain malware. And, any attempt to open the malicious attachments will result in the recipients getting their computers infected with a virus, Trojan horse, spyware, ransomware or other malware.
A Sample of a Malicious .ACE Email Message
Subject: 00_Invoice_7267
Date: Wed 17/05/2017 11:27
From: OMANRAJID
Attachment: 00_Invoice_7267.ace (108 KB)
The .ACE compression is similar to ZIP or RAR which is the most popular file compression or archive formats.
Cyber criminals usually store their malware in compressed files to help prevent antivirus software from detecting them. In other words, they do it because the compressed malicious email attachments may bypass the recipients' antivirus software.
What is an .ACE file?
Files that contain the .ace file extension are archive files that have been compressed using the WinAce file archiving utility. Computer users utilize a file archiving program when they want to combine a large batch of files into a single archive folder. WinAce is a program that can do this, utilizing a proprietary compression algorithm. This proprietary algorithm offers faster compression speeds and a higher compression ratio than many of the other archiving applications on the market. This allows the user to create smaller file archives, saving space on the user's hard drive.
The .ace file extension is also used by the Aces200 software program. This program uses the .ace file extension for the image files it saves.