T1036.003 Rename Legitimate Utilities

T1036.003 Rename Legitimate Utilities

Sub-technique of: T1036

High-Level Description

Adversaries may rename legitimate / system utilities to try to evade security mechanisms concerning the usage of those utilities. Security monitoring and control mechanisms may be in place for legitimate utilities adversaries are capable of abusing, including both built-in binaries and tools such as PSExec, AutoHotKey, and IronPython. It may be possible to bypass those security mechanisms by renaming the utility prior to utilization (ex: rename rundll32.exe). An alternative case occurs when a legitimate utility is copied or moved to a different directory and renamed to avoid detections based on these utilities executing from non-standard paths.

Kill Chain Phase

• Defense Evasion (TA0005)

Platforms: Linux, macOS, Windows

What to Check

• Identify if Rename Legitimate Utilities technique is applicable to target environment
• Check Linux systems for indicators of Rename Legitimate Utilities
• Check macOS systems for indicators of Rename Legitimate Utilities
• Check Windows systems for indicators of Rename Legitimate Utilities
• Verify mitigations are bypassed or absent (1 known mitigations)
• Assess detection coverage (1 detection strategies)

How to Test

Atomic Red Team Tests

The following tests are from Atomic Red Team and provide actionable ways to test this technique:

Atomic Test 1: Masquerading as Windows LSASS process

Copies cmd.exe, renames it, and launches it to masquerade as an instance of lsass.exe.

Upon execution, cmd will be launched by powershell. If using Invoke-AtomicTest, The test will hang until the 120 second timeout cancels the session

Supported Platforms: windows

copy %SystemRoot%\System32\cmd.exe %SystemRoot%\Temp\lsass.exe
%SystemRoot%\Temp\lsass.exe /B