General

  • Target

    BleedBootstrapper.exe

  • Size

    216KB

  • Sample

    240622-r344sswemp

  • MD5

    c985922fbfd599e853e51f20eb1c52af

  • SHA1

    2c1479539a4937c520d5352b245a9fdb01aa6d43

  • SHA256

    29b6d8b4e922d49e993bdd6cebc5370fb35ad1c8356188139a0c863825be98d6

  • SHA512

    8d1420a2b6c51a2bcd1aac3d1387b8f77539bfa9d3e73a8525e8b84439e76debb8081d07dc339415b811a8e0de7f6ccadca1ac6c248aecec4333be464431cc34

  • SSDEEP

    3072:LahKyd2n31d95GWp1icKAArDZz4N9GhbkrNEk5N7AX8VBt3wRW8IbE6Vx2K:LahO3p0yN90QEM

Malware Config

Extracted

Family

44caliber

C2

https://discord.com/api/webhooks/1169713279464120370/GUIw2wEmQMllUHEfRf3MNeS3DBNrZN-RuTQ9QbFfAqIZNVHtIlkj1yiD5QqgrIlv8gQi

Targets

    • Target

      BleedBootstrapper.exe

    • Size

      216KB

    • MD5

      c985922fbfd599e853e51f20eb1c52af

    • SHA1

      2c1479539a4937c520d5352b245a9fdb01aa6d43

    • SHA256

      29b6d8b4e922d49e993bdd6cebc5370fb35ad1c8356188139a0c863825be98d6

    • SHA512

      8d1420a2b6c51a2bcd1aac3d1387b8f77539bfa9d3e73a8525e8b84439e76debb8081d07dc339415b811a8e0de7f6ccadca1ac6c248aecec4333be464431cc34

    • SSDEEP

      3072:LahKyd2n31d95GWp1icKAArDZz4N9GhbkrNEk5N7AX8VBt3wRW8IbE6Vx2K:LahO3p0yN90QEM

    • 44Caliber

      An open source infostealer written in C#.

    • Identifies VirtualBox via ACPI registry values (likely anti-VM)

    • Downloads MZ/PE file

    • Modifies Windows Firewall

    • Checks BIOS information in registry

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

    • Executes dropped EXE

    • Loads dropped DLL

    • Reads user/profile data of web browsers

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

    • Themida packer

      Detects Themida, an advanced Windows software protection system.

    • Unexpected DNS network traffic destination

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

    • Accesses cryptocurrency files/wallets, possible credential harvesting

    • Adds Run key to start application

    • 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

    • Legitimate hosting services abused for malware hosting/C2

    • Looks up external IP address via web service

      Uses a legitimate IP lookup service to find the infected system's external IP.

    • Suspicious use of NtCreateThreadExHideFromDebugger

    • Suspicious use of NtSetInformationThreadHideFromDebugger

MITRE ATT&CK Enterprise v15

Tasks