General

  • Target

    f06b06c6332c2f6fa8ae2e650dd36ed70e850ac9a19ddf58193c357f0fbb349b

  • Size

    5.5MB

  • Sample

    250204-1nzefatpbw

  • MD5

    d39ebc382ec4e299ebfe7c2cc37677fc

  • SHA1

    b28d02f9d146248ef878a23d2cfba7c2be828795

  • SHA256

    f06b06c6332c2f6fa8ae2e650dd36ed70e850ac9a19ddf58193c357f0fbb349b

  • SHA512

    44647f02fe00af43767162ace5b86480e47c3ef7a625775a25895a817d2be1fa93acffa5767253422735891c6259fcb9baf1afb46407d8e53db68ecd10aaa51a

  • SSDEEP

    98304:RmBng9T/DSjSHtu4ffZN238DqQcBrcM7LacCmpfqAZekM5s3iD56lbSzfk:Y6DSjSHA4ffZI38kBPfacCmpCAZekM5c

Malware Config

Extracted

Family

quasar

Version

1.4.0.0

Botnet

Office

C2

45.87.154.103:4782

45.87.154.103:5552

Mutex

U79isvQ39fwJG6MYPN

Attributes
  • encryption_key

    cpXWTWxmR3Z0HXR8Fdwt

  • install_name

    csrss.exe

  • log_directory

    Logs

  • reconnect_delay

    3000

  • startup_key

    NET framework

  • subdirectory

    SubDir

Targets

    • Target

      f06b06c6332c2f6fa8ae2e650dd36ed70e850ac9a19ddf58193c357f0fbb349b

    • Size

      5.5MB

    • MD5

      d39ebc382ec4e299ebfe7c2cc37677fc

    • SHA1

      b28d02f9d146248ef878a23d2cfba7c2be828795

    • SHA256

      f06b06c6332c2f6fa8ae2e650dd36ed70e850ac9a19ddf58193c357f0fbb349b

    • SHA512

      44647f02fe00af43767162ace5b86480e47c3ef7a625775a25895a817d2be1fa93acffa5767253422735891c6259fcb9baf1afb46407d8e53db68ecd10aaa51a

    • SSDEEP

      98304:RmBng9T/DSjSHtu4ffZN238DqQcBrcM7LacCmpfqAZekM5s3iD56lbSzfk:Y6DSjSHA4ffZI38kBPfacCmpCAZekM5c

    • Quasar RAT

      Quasar is an open source Remote Access Tool.

    • Quasar family

    • Quasar payload

    • RevengeRAT

      Remote-access trojan with a wide range of capabilities.

    • Revengerat family

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

    • 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.

    • Deletes itself

    • Drops startup file

    • Executes dropped EXE

    • Loads dropped DLL

    • Checks whether UAC is enabled

    • Looks up external IP address via web service

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

    • Writes to the Master Boot Record (MBR)

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

    • Suspicious use of NtSetInformationThreadHideFromDebugger

    • Suspicious use of SetThreadContext

MITRE ATT&CK Enterprise v15

Tasks