Worm:W32/NetSky.E

Descriptions of previous NetSky variants can be found here:

• W32/NetSky.A@mm
• W32/NetSky.B@mm
• W32/NetSky.C@mm
• W32/NetSky.D@mm

The differences between NetSky.E variant and the .C variant of the worm are as follows:

• The worm's file is a PE executable file 24840 bytes long packed with Petite file compressor. The unpacked file's size is over 40 kilobytes.
• On March 2nd, 2004 the worm constantly beeps with PC speaker from 6:00 to 8:59. Below is the link to the WAV file with the sound that the worm makes: https://www.f-secure.com/virus-info/v-pics/netsky_d.wav
• The NetSky.E worm doesn't copy its files to shared folders.
• The NetSky.E worm variant uses 2 more extensions (.jpg and .gif) for the first extension (if double extension file name is generated) of its attachment: .txt .rtf .doc .htm .jpg .gif
• The .E worm variant uses 2 more extensions (.bat and .cmd) for the second extension (if double extension file name is generated) or for the only extension of its attachment: .exe .scr .com .pif .bat .cmd
• The .E worm variant has 2 more strings ('messagelabs' and 'skynet') added to the list of strings that it uses to avoid sending its emails to specified email addresses: icrosoft antivi ymantec spam avp f-secur itdefender orman cafee aspersky f-pro orton fbi abuse messagelabs skynet
• This variant has a bigger list of subjects: Delivery Failed Status report question trust me hey Re: excuse me read it immediatelly hi Re: does it? Yep important hello dear Re: unknown fake? warning moin what's up? info Re: information Here is it stolen private? good morning illegal... error take it re: Re: Re: Re: Re: you? something for you exception Re: hey excuse me Re: hi Re: does it? Re: important Re: hello believe me Question denied! notification Re: [5664ddff?$?? a 2] lol last chance! I'm back! its me notice! oh Announcement Re: Thank you Re: Details Thank you Details Re: Approved Approved hi, it's me Thank You very very much You use illegal... Your IP was logged Love is Re: [censored] registered? Your request was registered read now! Attention Schedule You have 1 day left Re: information automatic notification Expired account automatic responder Read this message please read please reply Registration confirm Confirmation Confirmation Required Returned Mail

The .E worm variant just like the .C variant spreads itself in emails as a ZIP attachment or as an executable attachment with one of the hardcoded names and single or double extension. A recipient has to unpack the worm's attachment from a ZIP archive and to run it or to run an executable attachment to get infected.

Like the .C variant, NetSky.E worm variant installs itself as WINLOGON.EXE file to Windows folder and creates a startup key for this file in the Registry:

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run] "ICQ Net" = "%windir%\winlogon.exe -stealth"

where %windir% represents Windows directory.

For more details, please see the description of NetSky.C worm variant.