Analysis

  • max time kernel
    140s
  • max time network
    169s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220812-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20220812-enlocale:en-usos:windows10-2004-x64system
  • submitted
    30-10-2022 13:58

General

  • Target

    打印共享修复Fix/LTSC/Fix_PrintSpooler.bat

  • Size

    1KB

  • MD5

    b4bcdad4dae1d57e6e38f81deb446e6e

  • SHA1

    40509574224f0610c65e127cfc19f1664136d905

  • SHA256

    7a7c4645e761205829d8c5490472b6d9371618ad5632ed96da29785496a0ee82

  • SHA512

    696392c468fe0a0e9d168946c154eff1f08df839cd35fe27102b80eb66bd8f95d9c9f9375fd35372c154628e1a5dcd132d5c6a6842af7eaf501d51c61d34485c

Malware Config

Signatures

  • Possible privilege escalation attempt 3 IoCs
  • Registers new Print Monitor 2 TTPs 12 IoCs
  • Loads dropped DLL 1 IoCs
  • Modifies file permissions 1 TTPs 3 IoCs
  • Drops file in System32 directory 2 IoCs
  • Checks SCSI registry key(s) 3 TTPs 12 IoCs

    SCSI information is often read in order to detect sandboxing environments.

  • Delays execution with timeout.exe 1 IoCs
  • Modifies data under HKEY_USERS 18 IoCs
  • Runs net.exe
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of WriteProcessMemory 18 IoCs

Processes

  • C:\Windows\system32\cmd.exe
    C:\Windows\system32\cmd.exe /c "C:\Users\Admin\AppData\Local\Temp\打印共享修复Fix\LTSC\Fix_PrintSpooler.bat"
    1⤵
    • Drops file in System32 directory
    • Suspicious use of WriteProcessMemory
    PID:1088
    • C:\Windows\system32\net.exe
      net stop spooler
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:1316
      • C:\Windows\system32\net1.exe
        C:\Windows\system32\net1 stop spooler
        3⤵
          PID:4004
      • C:\Windows\system32\timeout.exe
        timeout /t 3 /nobreak
        2⤵
        • Delays execution with timeout.exe
        PID:4200
      • C:\Windows\system32\takeown.exe
        Takeown /A /F C:\Windows\System32\win32spl.dll
        2⤵
        • Possible privilege escalation attempt
        • Modifies file permissions
        • Suspicious use of AdjustPrivilegeToken
        PID:2388
      • C:\Windows\system32\icacls.exe
        icacls "C:\Windows\System32\win32spl.dll" /grant "administrators":F
        2⤵
        • Possible privilege escalation attempt
        • Modifies file permissions
        PID:220
      • C:\Windows\system32\icacls.exe
        icacls "C:\Windows\System32\win32spl.dll" /grant SYSTEM:F
        2⤵
        • Possible privilege escalation attempt
        • Modifies file permissions
        PID:3116
      • C:\Windows\system32\reg.exe
        reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Print" /v RpcAuthnLevelPrivacyEnabled /t REG_DWORD /d 0 /f
        2⤵
          PID:1416
        • C:\Windows\system32\net.exe
          net start spooler
          2⤵
          • Suspicious use of WriteProcessMemory
          PID:1776
          • C:\Windows\system32\net1.exe
            C:\Windows\system32\net1 start spooler
            3⤵
              PID:3680
        • C:\Windows\System32\spoolsv.exe
          C:\Windows\System32\spoolsv.exe
          1⤵
          • Registers new Print Monitor
          • Loads dropped DLL
          • Checks SCSI registry key(s)
          • Modifies data under HKEY_USERS
          PID:3964

        Network

        MITRE ATT&CK Matrix ATT&CK v6

        Persistence

        Registry Run Keys / Startup Folder

        1
        T1060

        Defense Evasion

        Modify Registry

        1
        T1112

        File Permissions Modification

        1
        T1222

        Discovery

        Query Registry

        1
        T1012

        Peripheral Device Discovery

        1
        T1120

        System Information Discovery

        1
        T1082

        Replay Monitor

        Loading Replay Monitor...

        Downloads

        • C:\Windows\System32\win32spl.dll
          Filesize

          828KB

          MD5

          937dddf8be82ae84d207b7dea83ec6fd

          SHA1

          df86817c4a95283fe19d3be966cbc37282b5cbdc

          SHA256

          40bc894b387c867e8264bf9a3d3910cd1693fc1c8cb557f1a460607bf67d53d0

          SHA512

          0c5641f3e3d6cac2bfd12a258d45d4270d43a5b89ca50ffb2a414a1b3aa24ae0d0319f21ed90776cd2d00fac59c29b80ba0fb5372c585df99805bdca04f1c4b8

        • C:\Windows\System32\win32spl.dll
          Filesize

          828KB

          MD5

          937dddf8be82ae84d207b7dea83ec6fd

          SHA1

          df86817c4a95283fe19d3be966cbc37282b5cbdc

          SHA256

          40bc894b387c867e8264bf9a3d3910cd1693fc1c8cb557f1a460607bf67d53d0

          SHA512

          0c5641f3e3d6cac2bfd12a258d45d4270d43a5b89ca50ffb2a414a1b3aa24ae0d0319f21ed90776cd2d00fac59c29b80ba0fb5372c585df99805bdca04f1c4b8

        • memory/220-136-0x0000000000000000-mapping.dmp
        • memory/1316-132-0x0000000000000000-mapping.dmp
        • memory/1416-138-0x0000000000000000-mapping.dmp
        • memory/1776-139-0x0000000000000000-mapping.dmp
        • memory/2388-135-0x0000000000000000-mapping.dmp
        • memory/3116-137-0x0000000000000000-mapping.dmp
        • memory/3680-140-0x0000000000000000-mapping.dmp
        • memory/4004-133-0x0000000000000000-mapping.dmp
        • memory/4200-134-0x0000000000000000-mapping.dmp