Want to win a PS4? Go Premium and enter to win our High-Tech Treats giveaway. Enter to Win

x
?
Solved

lexical analysis and malware

Posted on 2009-03-31
2
Medium Priority
?
537 Views
Last Modified: 2013-11-22
Hello,

How can malware detection techniques can be related to lexical analysis ?

Thanks in advance for any info !
0
Comment
Question by:unknown_
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 6

Accepted Solution

by:
IKZ earned 2000 total points
ID: 24034911
Well just like every lexeme has a token associated with it to characterize it, so does a virus have a signature and it's "token" is a spot in the virus definition dictionary.  Signature based detection is the most common method that antivirus software uses to identify malware. This method is somewhat limited by the fact that it can only identify a limited amount of emerging threats, e.g. generic, or extremely broad, signatures.

For instance:
Lexeme: =    Token:  ASSIGN_OP
Lexeme: 5    Token:  NUMBER

Virus:  8 random character .dll file in system32 folder   Definition:  Vundo or Virtumonde

To the same effect, Tokenization is similar to the detection of viruses.
The first stage of lexical analysis is called the Scanner (just like in virus detection- it scans for certain things, like 8 random character .dll files in system32 folder like we talked about above.  Then the second stage in LA is called the evaluator.  Antivirus scanners do the same thing-- it finds data, usually broad, general or generic things, then evaluates or analyzes them and assigns them a value (virus or not).

Does this help at all?
0

Featured Post

Q2 2017 - Latest Malware & Internet Attacks

WatchGuard’s Threat Lab is a group of dedicated threat researchers committed to helping you stay ahead of the bad guys by providing in-depth analysis of the top security threats to your network.  Check out our latest Quarterly Internet Security Report!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

If you're a modern-day technology professional, you may be wondering if certifications are really necessary. They are. Here's why.
Ransomware, the malware that locks down its victim’s files until they pay up, has always been a frustrating issue to deal with. However, a recent mobile ransomware will make the issue a little more personal… by sharing the victim’s mobile browsing h…
Sending a Secure fax is easy with eFax Corporate (http://www.enterprise.efax.com). First, Just open a new email message.  In the To field, type your recipient's fax number @efaxsend.com. You can even send a secure international fax — just include t…
This video Micro Tutorial shows how to password-protect PDF files with free software. Many software products can do this, such as Adobe Acrobat (but not Adobe Reader), Nuance PaperPort, and Nuance Power PDF, but they are not free products. This vide…

618 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question