As part of our commitment to your online security and privacy, we block the following types of file attachments in emails. These attachments are removed from emails before delivery to you and placed in a quarantine area for 30 days in case 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 are 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 (e.g., A977FF0C-8757-4E76-8533-482F91946233)

# 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 (e.g., .txt.pif, .doc.pif, .doc.com, .txt.exe)
                  

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