General

  • Target

    7z2406-x64.exe

  • Size

    1.5MB

  • Sample

    240613-b72w8stdml

  • MD5

    d8af785ca5752bae36e8af5a2f912d81

  • SHA1

    54da15671ad8a765f3213912cba8ebd8dac1f254

  • SHA256

    6220bbe6c26d87fc343e0ffa4e20ccfafeca7dab2742e41963c40b56fb884807

  • SHA512

    b635b449f49aac29234f677e662be35f72a059401ea0786d956485d07134f9dd10ed284338503f08ff7aad16833cf034eb955ca34e1faf35a8177ccad1f20c75

  • SSDEEP

    49152:6E+lvaQr7omhpcibOw1eLmz6O92u3RtRj08+Z3bG:6EzQ3/hdSzLVO92uTRmZy

Malware Config

Targets

    • Target

      7z2406-x64.exe

    • Size

      1.5MB

    • MD5

      d8af785ca5752bae36e8af5a2f912d81

    • SHA1

      54da15671ad8a765f3213912cba8ebd8dac1f254

    • SHA256

      6220bbe6c26d87fc343e0ffa4e20ccfafeca7dab2742e41963c40b56fb884807

    • SHA512

      b635b449f49aac29234f677e662be35f72a059401ea0786d956485d07134f9dd10ed284338503f08ff7aad16833cf034eb955ca34e1faf35a8177ccad1f20c75

    • SSDEEP

      49152:6E+lvaQr7omhpcibOw1eLmz6O92u3RtRj08+Z3bG:6EzQ3/hdSzLVO92uTRmZy

    • Chaos

      Ransomware family first seen in June 2021.

    • Chaos Ransomware

    • UAC bypass

    • Deletes shadow copies

      Ransomware often targets backup files to inhibit system recovery.

    • Modifies boot configuration data using bcdedit

    • Deletes backup catalog

      Uses wbadmin.exe to inhibit system recovery.

    • Disables Task Manager via registry modification

    • Downloads MZ/PE file

    • Checks computer location settings

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

    • Drops startup file

    • 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.

    • Registers COM server for autorun

    • UPX packed file

      Detects executables packed with UPX/modified UPX open source packer.

    • Checks installed software on the system

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

    • Drops desktop.ini file(s)

    • 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.

    • Sets desktop wallpaper using registry

MITRE ATT&CK Enterprise v15

Tasks