MSFE for Users – Dangerous Attachments

The following is a list of some of the file attachments that may be blocked by the service (the attachments are removed from emails before delivery to you and may be placed in a quarantine area for a few days should you wish to receive them):

# These are known to be dangerous in almost all cases.
.reg Possible Windows registry attack
.chm Possible compiled Help file-based virus
.cnf Possible SpeedDial attack
.hta Possible Microsoft HTML archive attack
.ins Possible Microsoft Internet Comm. Settings attack
.jse_ Possible Microsoft JScript attack
.lnk Possible Eudora *.lnk security hole attack
.ma_ Possible Microsoft Access Shortcut attack
.pif Possible MS-Dos program shortcut attack
.scf Possible Windows Explorer Command attack
.sct Possible Microsoft Windows Script Component attack
.shb Possible document shortcut attack
.shs Possible Shell Scrap Object attack
.vbe or .vbs Possible Microsoft Visual Basic script attack
.wsc .wsf .wsh Possible Microsoft Windows Script Host attack
.xnk Possible Microsoft Exchange Shortcut attack

# These 2 added by popular demand – Very often used by viruses
.com Windows/DOS Executable
.exe Windows/DOS Executable

# These are very dangerous and have been used to hide viruses
.scr Possible virus hidden in a screensaver
.bat Possible malicious batch file script
.cmd Possible malicious batch file script
.cpl Possible malicious control panel item
.mhtml Possible Eudora meta-refresh attack

# Deny filenames ending with CLSID’s
{[a-hA-H0-9-]{25,}\} Filename trying to hide its real extension
Examples:
A977FF0C-8757-4E76-8533-482F91946233
000209FF-0000-0000-C000-000000000046

# Deny filenames with lots of contiguous white space in them.
Filename contains lots of white space

# Deny all other double file extensions. This catches any hidden filenames.
Found possible filename hiding
Examples:
.txt.pif
.doc.pif
.doc.com
.txt.exe

We are taking a short break and will close the store, helpdesk and email from Wednesday, 30 November through Tuesday, 6 December 2022.

If you purchase a license or Service Package before the closing date and require installation, please be sure to leave at least 24 hours before then for the work to be done. Otherwise, any work will be scheduled for after this period. We will reopen on Wednesday, 7 December 2022.