I received a notice that a message contains a high risk zip attachment. What does this mean?
High Risk Zip Attachment Info
ZIP is a commonly used form of file compression. ZIP files generally contain other files and folders, and ZIP archives may not always have a .zip extension (ie- Microsoft Word DOCX files).
Certain programs (MS Office 2007+, Adobe Acrobat 10+, et al.) use ZIP compression in their document formats, and the McAfee SaaS Email Protection service may identify these files as ZIP archives.
Highly compressed ZIP files that contain large files or deeply nested folders will take additional time for our virus scanners to process. As a result, the message may be delayed by a few minutes while it is processed by our virus scanning engines.
A ZIP attachment will be considered high risk if it violates any of the following rules:
- The zip file itself is too large (> 500MB)
- A file contained in the zip file is too large (> 100MB)
- The zip file contains too many files (> 1500 files)
- The compression rate is too high (> 95% compressed)
- The zip file contains too many levels of nesting (> 3 levels)