7-Zip Archive (.7z) Malicious Email Attachments
Online users who have received unexpected email messages with attached files with names ending with ".7z" are asked not to open them. This is because the fake email messages are being sent by cyber criminals and the attachments are 7-Zip compressed archived files that contain malware, malicious programs or computer viruses. 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 7-Zip Archive (.7z) Email Message
Subject: Emailed Invoice - 107681:1
Date: Wed 30/08/2017 22:04
From: Nickolas Leonard
Attachment: I_107681-1.7z (3 KB)
As requested
regards
--
Nickolas Leonard
The 7-Zip compression is similar to ZIP 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 a 7-Zip file?
Files with the extension .7z are compressed archive files created with 7-Zip open source software. These files are created using a compression method called LZMA, which is an algorithm for lossless data compression—a type of compression known for reducing file size while preserving quality.
Check the comment section below for additional information, share what you know or ask a question about this article by leaving a comment below. And, to quickly find answers to your questions, use our search
engine.
Click here help maintain Online Threat Alerts (OTA).
Note: Some of the information in samples on this website may have been impersonated or spoofed.
Would you share this article with others? +
Comments, Questions, Answers, or Reviews
To protect your privacy, please do not post or remove sensitive information in or from your comments, questions, or reviews.
Advertisement
Show More Comments (8)
Write Your Comment, Question, Answer, or Review
NB: We will use your IP address to display your approximate location to other users.
Recommendations / Ads