OpenRCE

About Articles Book Store Distributed RCE Downloads Event Calendar Forums Live Discussion Reference Library RSS Feeds Search Store Users What's New

Customize Theme

Flag: Tornado! Hurricane!

Article Abstract The W32.Evol virus was discovered around July 2000. Its name is derived from a string found in the virus, but much more can be implied from the name. Up until then, most of the viruses were using Polymorphic engines in order to hide themselves from Anti-Virus scanners. The engine would encrypt the virus with a different key on every generation, and would generate a small, variant decryptor that would consist of different operations but remain functionally equivalent. This technique was beginning to wear out as AV scanners would trace virus-decryption until it was decrypted in memory, visible and clear.

This article explores the features and functionality of the metamorphic engine of the Evol virus, the first virus to utilize a 'true' metamorphic engine according to Symantec.

Full Article ...

Printer Friendly ...

Article Comments

nico	Posted: Wednesday, February 21 2007 15:35.17 CST
Good work, interesting disassembly :)

eraser	Posted: Monday, March 12 2007 11:13.59 CDT
Many thanks for your valuable contribution.

MazeGen	Posted: Friday, March 30 2007 02:57.38 CDT
Very interesting article, thanks. There's one error in chapter "II. Alternative Instruction Encoding": EB imm8 is JMP short (there's nothing like CALL short).

eraser	Posted: Wednesday, April 4 2007 13:33.07 CDT
You are right MazeGen. `EB cb JMP cb Jump short (signed byte relative to next instruction) E9 cv JMP cv Jump near (vword offset relative to next instruction)`

Orr	Posted: Friday, April 6 2007 16:02.00 CDT
The mistake is in the paper and not in the engine. You can refer to the label 'isJccShort' in the disassembly.

adityaks	Posted: Wednesday, June 20 2007 06:07.58 CDT
nice one man

nEINEI	Posted: Friday, November 27 2009 04:04.08 CST
good work~~

zhxia	Posted: Tuesday, August 10 2010 01:27.25 CDT
There's one error in chapter "II. Alternative Instruction Encoding": EB imm8 is JMP short (there's nothing like CALL short). http://www.linksjewelleryin.com/

zhxia	Posted: Tuesday, August 10 2010 01:27.39 CDT
<strong><a href="http://www.linksjewelleryin.com/">links london</a></strong> <strong><a href="http://www.linksjewelleryin.com/">links of london bracelets</a></strong> <strong><a href="http://www.linksjewelleryin.com/">links of london jewellery</a></strong>

zhxia	Posted: Tuesday, August 10 2010 01:27.47 CDT
url=http://www.eluxurys-store.com/]buy gucci watches[/url] gucci sale louis vuitton

Active in Last 5 Minutes
	excavationfondations
	bigines

There are 21,678 total registered users.

Recently Created Topics
PyEmu error when cal...	Sep/02
Restore Themida/Winl...	Sep/02
Anti-olly technique	Aug/30
RAR Password	Aug/29
Heap protection on W...	Aug/23
Why Inline asm in C+...	Aug/20
Bypassing OllyAdvance	Aug/17
Error in logic for g...	Aug/17
Has anyone seen this...	Aug/17
ARM Executable - Pat...	Aug/16

Recent Forum Posts
reverse engineering ...	raiden56
pydbg, memory breakp...	Researc...
RAR Password	Ineedhelp
RAR Password	cod
Heap protection on W...	voila
Heap protection on W...	j00ru
Heap protection on W...	voila
Heap protection on W...	j00ru
Heap protection on W...	psylocn
Why Inline asm in C+...	ronnie2...

Recent Blog Entries
	meshmesh	Sep/01
Is it legal??
	waleedassar	Aug/30
Anti-olly technique
	QvasiModo	Aug/24
WinAppDbg 1.4 is out!
	artemblagodarenko	Aug/18
Dataflow-0.2.0 released. Ne...
	grzonu	Aug/17
Bypassing OllyAdvanced
More ...

Recent Blog Comments
	tosanjay on:	Sep/02
PyEmu 0.0.2
	GynvaelColdwind on:	Sep/01
Is it legal??
	PeterFerrie on:	Aug/31
Anti-olly technique
	dennis on:	Aug/26
Dr. Gadget IDAPython plugin
	halsten on:	Aug/19
Dataflow-0.2.0 released. Ne...
More ...

Imagery

SoySauce Blueprint
Jun 6, 2008

[+] expand

View Gallery (11) / Submit