Computer security experts warned the virus will activate for the first time this Friday and will destroy the files of most popular formats with the extensions ".doc, .xls, .ppt, .zip, .rar, . pdf, .psd and .dmp".

The virus' main objective is to destroy files and may permanently delete or corrupt text documents and images among others.

However, according to the anti-virus company Symantec, this is a low spreading virus, the "Troy Horse" kind, different to worms able to re-invent themselves throughout e-mail listings from for a quick spreading.

The virus infects systems when found within a file disguised as picture or any other content that may be downloaded directly from the web or may be hiding in an e-mail.

At first, "Blackworm" was estimated to have infected millions of computers in the world but it was the same virus which disclosed the numbers of its reach.

"Blackworm" has a distinctive characteristic which is to report to a server with a counter each system infected by it so that its damage and extension is recorded.

The Lurhq security firm, which has monitored the virus, informed that until last Sunday the virus has just infected some 300 thousand computers in the world and that this figure did not go up in numbers that quickly.

According to analysts' estimates, the virus will have infected some 600 thousand computers by this next Friday when it will go off for the first time to later on do the same every third days of a month.

These numbers are considered as low in comparison to the dozens of active computers in the world and plugged to the Internet.

Specialists warn users must update their anti-virus programs and never open unknown files in order to prevent their systems from getting infected.

Vendor Malware Name

Authentium W32/Kapser.A@mm
AntiVir Worm/KillAV.GR
Avast! Win32:VB-CD [Wrm]
AVG Worm/Generic.FX
BitDefender Win32.Worm.P2P.ABM
ClamAV Worm.VB-8
Command W32/Kapser.A@mm (exact)
Dr Web Win32.HLLM.Generic.391
eSafe Win32.VB.bi
eTrust-INO Win32/Blackmal.F!Worm
eTrust-VET Win32/Blackmal.F
Ewido Worm.VB.bi
F-Prot W32/Kapser.A@mm (exact)
F-Secure Email-Worm.Win32.Nyxem.e
Fortinet W32/Grew.A!wm
Ikarus Email-Worm.Win32.VB.BI
Kaspersky Email-Worm.Win32.Nyxem.e
McAfee W32/MyWife.d@MM
Nod32 Win32/VB.NEI worm
Norman W32/Small.KI (W32/Small.KI@mm)
Panda W32/Tearec.A.worm (W32/MyWife.E.Worm)
QuickHeal I-Worm.Nyxem.e
Sophos W32/Nyxem-D
Symantec W32.Blackmal.E@mm
Trend Micro WORM_GREW.A (Worm_BLUEWORM.E)
VBA32 Email-Worm.Win32.VB.bi  dedicated server mumbai
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