General

  • Target

    .

  • Size

    147KB

  • Sample

    240514-sd48yabg6s

  • MD5

    5670124ebca90d95d1a3aa2d46da9c13

  • SHA1

    2d7fe9f235ae1ba5110c50ba857617bf555b71a0

  • SHA256

    bf8bf13b893d190fd27bd23990c52933f2b265bb2e6834578f9eba19844e8435

  • SHA512

    9275df0cfa982c1ae557f79ca29ff7702e0696d1b02515fc78d7d2c4b52389ac02e346edb2adda949e681f1173c591ec702dfd51b111fbf0bcacfa706eb264c6

  • SSDEEP

    1536:oVkud8TPV9vK4DNvGR4Dbll1qKf+30vD932Os4DjHhqiS:+kPT3V+CllQHKNHhqiS

Malware Config

Extracted

Family

crimsonrat

C2

185.136.161.124

Targets

    • Target

      .

    • Size

      147KB

    • MD5

      5670124ebca90d95d1a3aa2d46da9c13

    • SHA1

      2d7fe9f235ae1ba5110c50ba857617bf555b71a0

    • SHA256

      bf8bf13b893d190fd27bd23990c52933f2b265bb2e6834578f9eba19844e8435

    • SHA512

      9275df0cfa982c1ae557f79ca29ff7702e0696d1b02515fc78d7d2c4b52389ac02e346edb2adda949e681f1173c591ec702dfd51b111fbf0bcacfa706eb264c6

    • SSDEEP

      1536:oVkud8TPV9vK4DNvGR4Dbll1qKf+30vD932Os4DjHhqiS:+kPT3V+CllQHKNHhqiS

    • CrimsonRAT main payload

    • CrimsonRat

      Crimson RAT is a malware linked to a Pakistani-linked threat actor.

    • Modifies WinLogon for persistence

    • Modifies Windows Defender Real-time Protection settings

    • Suspicious use of NtCreateUserProcessOtherParentProcess

    • UAC bypass

    • Modifies boot configuration data using bcdedit

    • Downloads MZ/PE file

    • Drops file in Drivers directory

    • Modifies Installed Components in the registry

    • Modifies RDP port number used by Windows

    • Office macro that triggers on suspicious action

      Office document macro which triggers in special circumstances - often malicious.

    • Sets service image path in registry

    • Checks BIOS information in registry

      BIOS information is often read in order to detect sandboxing environments.

    • Checks computer location settings

      Looks up country code configured in the registry, likely geofence.

    • Executes dropped EXE

    • Loads dropped DLL

    • Modifies system executable filetype association

    • Reads user/profile data of web browsers

      Infostealers often target stored browser data, which can include saved credentials etc.

    • Registers COM server for autorun

    • Unexpected DNS network traffic destination

      Network traffic to other servers than the configured DNS servers was detected on the DNS port.

    • Adds Run key to start application

    • Checks for any installed AV software in registry

    • Checks installed software on the system

      Looks up Uninstall key entries in the registry to enumerate software on the system.

    • Checks whether UAC is enabled

    • Drops desktop.ini file(s)

    • Enumerates connected drives

      Attempts to read the root path of hard drives other than the default C: drive.

    • Legitimate hosting services abused for malware hosting/C2

    • Writes to the Master Boot Record (MBR)

      Bootkits write to the MBR to gain persistence at a level below the operating system.

    • AutoIT Executable

      AutoIT scripts compiled to PE executables.

    • Checks system information in the registry

      System information is often read in order to detect sandboxing environments.

    • Drops file in System32 directory

MITRE ATT&CK Matrix ATT&CK v13

Persistence

Boot or Logon Autostart Execution

5
T1547

Registry Run Keys / Startup Folder

4
T1547.001

Winlogon Helper DLL

1
T1547.004

Create or Modify System Process

1
T1543

Windows Service

1
T1543.003

Event Triggered Execution

1
T1546

Change Default File Association

1
T1546.001

Pre-OS Boot

1
T1542

Bootkit

1
T1542.003

Privilege Escalation

Boot or Logon Autostart Execution

5
T1547

Registry Run Keys / Startup Folder

4
T1547.001

Winlogon Helper DLL

1
T1547.004

Create or Modify System Process

1
T1543

Windows Service

1
T1543.003

Abuse Elevation Control Mechanism

1
T1548

Bypass User Account Control

1
T1548.002

Event Triggered Execution

1
T1546

Change Default File Association

1
T1546.001

Defense Evasion

Modify Registry

9
T1112

Impair Defenses

2
T1562

Disable or Modify Tools

2
T1562.001

Abuse Elevation Control Mechanism

1
T1548

Bypass User Account Control

1
T1548.002

Pre-OS Boot

1
T1542

Bootkit

1
T1542.003

Subvert Trust Controls

1
T1553

Install Root Certificate

1
T1553.004

Credential Access

Unsecured Credentials

1
T1552

Credentials In Files

1
T1552.001

Discovery

Query Registry

9
T1012

System Information Discovery

10
T1082

Software Discovery

1
T1518

Security Software Discovery

1
T1518.001

Peripheral Device Discovery

2
T1120

Lateral Movement

Remote Services

1
T1021

Remote Desktop Protocol

1
T1021.001

Collection

Data from Local System

1
T1005

Command and Control

Web Service

1
T1102

Impact

Inhibit System Recovery

1
T1490

Tasks