General

  • Target

    tmk.scr

  • Size

    538KB

  • Sample

    240829-xdyhlsxfjp

  • MD5

    f257d37c05d29e725071a900ef49f1c9

  • SHA1

    11fa3fc864d53a90cd4ed3c4e3e3aba3c7890fae

  • SHA256

    aaf3cf701b06ca873f9fdbf5b4ba33722c6ecea49316a344df35926a45bce1fb

  • SHA512

    945ce0d2305183bf5ab19a563259d9f8cf39b115608f254c15e8d29cc542807290975d49b8de344400493f106e23a196a92f0197154719a49d5c3ff684cd8fab

  • SSDEEP

    3072:6XpAi2YcRVm16Pn6n0H7GMgXuD//bFLAkC8htEyR/x5Zt19r0d/rFLjZkJ:6XpAiWm16yaGMVFLQmEFFL2

Malware Config

Targets

    • Target

      tmk.scr

    • Size

      538KB

    • MD5

      f257d37c05d29e725071a900ef49f1c9

    • SHA1

      11fa3fc864d53a90cd4ed3c4e3e3aba3c7890fae

    • SHA256

      aaf3cf701b06ca873f9fdbf5b4ba33722c6ecea49316a344df35926a45bce1fb

    • SHA512

      945ce0d2305183bf5ab19a563259d9f8cf39b115608f254c15e8d29cc542807290975d49b8de344400493f106e23a196a92f0197154719a49d5c3ff684cd8fab

    • SSDEEP

      3072:6XpAi2YcRVm16Pn6n0H7GMgXuD//bFLAkC8htEyR/x5Zt19r0d/rFLjZkJ:6XpAiWm16yaGMVFLQmEFFL2

    • Chaos

      Ransomware family first seen in June 2021.

    • Chaos Ransomware

    • Suspicious use of NtCreateProcessExOtherParentProcess

    • Downloads MZ/PE file

    • Drops file in Drivers directory

    • Sets service image path in registry

    • Checks computer location settings

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

    • Event Triggered Execution: Component Object Model Hijacking

      Adversaries may establish persistence by executing malicious content triggered by hijacked references to Component Object Model (COM) objects.

    • Executes dropped EXE

    • Impair Defenses: Safe Mode Boot

    • Loads dropped DLL

    • Reads user/profile data of web browsers

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

    • Windows security modification

    • 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.

    • Writes to the Master Boot Record (MBR)

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

    • Drops file in System32 directory

MITRE ATT&CK Enterprise v15

Tasks