General

  • Target

    PolyBuilds_1v1.exe

  • Size

    7KB

  • Sample

    241230-rlpb1sxjfm

  • MD5

    2fae942335ec0270cbe0e8496fe5bdfd

  • SHA1

    b80444b8f5cb7bd4722b45fe15438762df20b443

  • SHA256

    c2da68ac7342ec39b1a6fd5c5688a81d6cf40cee65ab1653c72cdc6d302fa51c

  • SHA512

    3b2a01d380940c07030292aca7ac0ca38980e8cd58bdb255f853b6a84309c11beb6ef16249bf96beee039cfa888b5b62963bb2b507019041f17c067b63d4d6a2

  • SSDEEP

    96:TJWv2mqCKMrvJSA/Z7YR8mH7sRPOlkjDt/MpmPBoYbiMvZpV3Q1Rf+p6G:Ty2MjJ9HmbshOwVYyr/3V3QDf+

Malware Config

Extracted

Family

xworm

Attributes
  • Install_directory

    %AppData%

  • install_file

    RtkAudUService64.exe

  • pastebin_url

    https://pastebin.com/raw/6ZBHT1SN

Targets

    • Target

      PolyBuilds_1v1.exe

    • Size

      7KB

    • MD5

      2fae942335ec0270cbe0e8496fe5bdfd

    • SHA1

      b80444b8f5cb7bd4722b45fe15438762df20b443

    • SHA256

      c2da68ac7342ec39b1a6fd5c5688a81d6cf40cee65ab1653c72cdc6d302fa51c

    • SHA512

      3b2a01d380940c07030292aca7ac0ca38980e8cd58bdb255f853b6a84309c11beb6ef16249bf96beee039cfa888b5b62963bb2b507019041f17c067b63d4d6a2

    • SSDEEP

      96:TJWv2mqCKMrvJSA/Z7YR8mH7sRPOlkjDt/MpmPBoYbiMvZpV3Q1Rf+p6G:Ty2MjJ9HmbshOwVYyr/3V3QDf+

    • Detect Xworm Payload

    • Suspicious use of NtCreateUserProcessOtherParentProcess

    • Xworm

      Xworm is a remote access trojan written in C#.

    • Xworm family

    • Downloads MZ/PE file

    • 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

    • Indicator Removal: Clear Windows Event Logs

      Clear Windows Event Logs to hide the activity of an intrusion.

    • Command and Scripting Interpreter: PowerShell

      Using powershell.exe command.

    • 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

    • 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.

    • Drops file in System32 directory

    • Suspicious use of SetThreadContext

MITRE ATT&CK Enterprise v15

Tasks