ExploreZip


ExploreZip, also known as I-Worm.ZippedFiles is a destructive computer worm that attacks machines running Microsoft Windows. It was first discovered in Israel on June 6, 1999. Worm.ExploreZip is a worm that contains a malicious payload. The worm utilizes Microsoft Outlook, Outlook Express, or Exchange to mail itself out by replying to unread messages in your Inbox. The email attachment is Zipped_files.exe. The worm also searches mapped drives and networked computers for Windows installations. If found, it copies itself to the \Windows folder of the remote computer and then modifies the Win.ini file of the infected computer. On January 8, 2003, Security Response discovered a packed variant of this threat which exhibits the same characteristics.

Distribution

It is distributed in the form of an e-mail message with the words:
Hi!
I have received your email and I shall send you a reply ASAP. Till then take a look at the attached zipped docs.
Bye!

Payload

The message includes an attachment with the name ZIPPED_FILES.EXE. If opened, a dialog box appears in Windows resembling the one normally appearing when opening a corrupted Zip archive, while the worm copies itself onto the machine's hard drive. It also modifies the WIN.INI file or the Windows Registry so that it re-executes on reboot.
The worm looks for a copy of Microsoft Outlook to mail itself to all other people in the user's address book and also destroys Microsoft Office documents and C and C++ source files on the user's hard drive by overwriting them with zero-byte files.