Web Attacks using 
Obfuscated JavaScript 
Amol Kamble
“ Code obfuscation is the practice of 
making code unintelligible , or at the 
very least, hard to understand ” 
“General code obfuscation techniques 
aim to confuse the understanding of 
the way in which program functions.”
Who use the Code Obfuscation? 
code obfuscation is used to protect 
intellectual property by software 
companies. 
it is also used extensively by authors 
of malicious code to avoid detection 
from virus scanner.
Different Obfuscation Techniques
Different Obfuscation Techniques 
Randomization Obfuscation 
Data Obfuscation 
Encoding Obfuscation 
Logic Structure Obfuscation
Obfuscation Examples 
obfuscate a loop
Obfuscation Examples
Use of Script In Web
Use of Scripts In Web 
Information Validation 
Event Handling 
Changing Web Content 
Dynamically 
Business Logic Implementation
Use of Scripts by the Web 
Attacker
Use of Scripts by the Web 
Attacker 
Information Loss 
Download Malicious Code 
Redirect to Another Malicious 
Website 
Doing something Behalf of User 
Calling Native Function
How antivirus software works
How antivirus software works 
Signature-based detection 
Behavioral detection 
String pattern Matching 
Emulator or Virual Browser
How antivirus Deal with 
Malicious Obfuscated Script
How antivirus Deal with 
Malicious Obfuscated Script 
Deobfuscate the Script and 
Check for virus Signature 
Don’t Allowed any Obfuscated 
Script
How antivirus Deal with 
Malicious Obfuscated Script 
Run Script in Virtual Browser and 
Check Script Behaviour 
Deobfusated the Script and 
Check Semantics of Instrution in 
Script
Thank you!!!

Web attacks using obfuscated script