229. That's How UAT-7237 Interacts with Windows Registry

Hello everyone!

Windows Registry contains lots of sensitive information and configurations, so adversaries often interact with it. Today we'll look at two examples!

And we'll extract both procedures from this report. The first technique is Registry Modification (T1112). The adversary used it to disable User Account Control (UAC) restriction:

reg add HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\system /v LocalAccountTokenFilterPolicy /t REG_DWORD /d 1 /f

We can build detection based on reg.exe abuse or just value modification itself:

event_type: "registryvalueset"

AND

reg_key_path: "LocalAccountTokenFilterPolicy"

AND

reg_value_data: "0x00000001"

The second technique - Unsecured Credentials: Credentials in Registry (T1552.002). The adversary queried the Registry to obtain VNC credentials:

reg query "HKCU\Software\ORL\WinVNC3\Password"

Let's build the detection based on reg.exe abuse this time:

event_type: "processcreatewin"

AND

proc_file_path: "reg.exe"

AND

cmdline: ("winvnc3" AND "password")

See you tomorrow!

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