Static Unpacking For The Widespread NSIS-Based Malicious Packer Family


Packers or crypters are widely used to protect malicious software from detection and static analysis. These auxiliary tools, through the use of compression and encryption algorithms, enable cybercriminals to prepare unique samples of malicious software for each campaign or even per victim, which complicates the work of antivirus software.

In the case of certain packers, classifying malicious software without employing dynamic analysis becomes a challenging task. To analyze a malicious sample and extract its configuration data, such as encryption keys and command and control server addresses, we must first unpack it. We can do this by running the malicious software in a sandbox environment, such as CAPE, followed by extracting the memory dumps. However, this method has some drawbacks.

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Source: Check Point


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