243. NetSupport RAT: The Most Prevalent Threat of August 2025

Hello everyone!

Remote Access Tools (T1219) is still a very common technique observed in many campaigns and incidents. According to Red Canary's Intelligence Insights for August 2025, the most prevalent threat was NetSupport RAT, so let's look at various detection opportunities.

As always, adversaries may rename executables. So we can search for rename NetSupport executables:

event_type: "processcreatewin"

AND

proc_file_productname: "netsupport"

AND NOT

proc_file_path: "client32.exe"

Next thing, normally the RAT should start from the Program Files directory, so we can search for running it from other folders:

event_type: "processcreatewin"

AND

proc_file_path: "client32.exe"

AND NOT

proc_file_path: "program files"

Finally, we can look for network indicators:

event_type: "dnsreqwin"

AND

dns_rname: "netsupportsoftware.com"

See you tomorrow!

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