083. Detecting Ransomware Affiliate's Toolkit: HRSword

Hello everyone! Let's talk about another tool in ransomware affiliate's arsenal. This time it's going to be HRSword! Usually adversaries use it to disable the target machine’s defenses.

For example, according to this report, the tool was used by Helldown ransomware affiliates to monitor and terminate security-related processes.

Let's start from the binary itself, and create a detector based on its metadata:

event_type: "processcreatewin" 

AND 

proc_file_originalfilename: "HRSword.exe"

It also abuses cmd.exe to copy multiple files to "C:\Windows\System32\drivers\", for example:

cmd.exe /S /D /c" copy Drivers\x32\sysdiag.sys "C:\Windows\System32\drivers\"

Here we can use the following logic:

event_type: "processcreatewin" 

AND

proc_file_name: "cmd.exe"

AND

cmdline: ("copy" AND "drivers")

Want more detection opportunities? Check the sample!

See you tomorrow!


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