• Journal of Digital Contents Society
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• v.15 no.3
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• pp.373-380
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• 2014

Malicious codes uses generic unpacking technique to make it hard for analyzers to detect their programs. Recently their has been several researches about generic packet to prevent or detect these techniques. And they try to focus on the codes that repeats while generic packing is doing compression because generic packing technique executes after it is decompressed. And they try to focus on the codes that repeats while generic packing is doing compression because generic packing technique executes after it is decompressed. Therefore, this makes a interesting performance which shows a similar address value from the codes which are repeated several times what is different from the normal program codes. By dividing these codes into regularly separated areas we can find that the generic unpacking codes have a small entropy value compared to normal codes. Using this method, it is possible to identify any program if it is a generic unpacking code or not even though we do not know what kind of algorithm it uses. This paper suggests a way of disarming the generic codes by using the low value entropy value which comes out from the Opcode addresses when generic unpacking codes try to decompress.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.2
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• pp.179-188
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• 2012

Packing techniques, one of malicious code detection and analysis avoidance techniques, change code to reduce size and make analysts confused. Therefore, malwares have more time to spread out and it takes longer time to analyze them. Thus, these kind of unpacking techniques have been studied to deal with packed malicious code lately. Packed programs are unpacked during execution. When it is unpacked, the data inside of the packed program are changed. Because of these changes, the entropy value of packed program is changed. After unpacking, there will be no data changes; thus, the entropy value is not changed anymore. Therefore, packed programs could be unpacked finding the unpacking point using this characteristic regardless of packing algorithms. This paper suggests the generic unpacking mechanism using the method estimating the unpacking point through the variation of entropy values.

• Convergence Security Journal
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• v.5 no.3
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• pp.75-86
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• 2005

Recently, illegal manipulation and forgery threats on computer softwares are increasing due to the advances in reverse engineering techniques. Furthermore someone who has concerns about these area can crack the software by using the open-to-public simple tools on the internet. The software companies are struggling to defend their own softwares against threats, while the crackers are continuing to crack the softwares. In this paper, we first establish the generic software threat model and, analyze and experiment on the software cracks, before suggest a memory hacking prevention system in Microsoft Windows environment.

• Journal of Advanced Navigation Technology
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• v.17 no.5
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• pp.545-551
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• 2013

Packed technique makes difficult to respond quickly because the malicious-code is reduced size that easy to diffusion and changed code that make spend longer time for analysis. In this paper, we analysed the packing tool softwares and we proposed construction and detection methods of the packed technique for easy to analysis of the packed malicious code based on variation of entropy value.