Created the Saturday 23 March 2019. Updated 7 months ago.

Suspending threads is a technique used by malware to disable user-mode debuggers and make it more difficult for security analysts to reverse engineer and analyze the code. This can be achieved by using the SuspendThread function from the kernel32.dll library or the NtSuspendThread function from the NTDLL.DLL library.

The malware can enumerate the threads of a given process, or search for a named window and open its owner thread, and then suspend that thread. This will prevent the debugger from running and make it more difficult to analyze the code.

This technique can be used by malware authors to evade detection and analysis, and make their code more difficult to understand.

Featured Windows API's

Below, you will find a list of the most commonly used Windows API's that are currently utilized by malware authors for current evasion technique. This list is meant to provide an overview of the API's that are commonly used for this purpose. If there are any API's that you feel should be included on this list, please do not hesitate to contact us. We will be happy to update the list and provide any additional information or documentation that may be helpful.

Code Snippets

Detection Rules

Additional Resources

External Links

The resources provided below are associated links that will give you even more detailed information and research on current evasion technique. It is important to note that, while these resources may be helpful, it is important to exercise caution when following external links. As always, be careful when clicking on links from unknown sources, as they may lead to malicious content.

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