Analysis

  • max time kernel
    148s
  • max time network
    149s
  • platform
    windows10_x64
  • resource
    win10v20210410
  • submitted
    29-04-2021 06:29

General

  • Target

    ef8bf0e0c08418ed74b33120185fd044.exe

  • Size

    219KB

  • MD5

    ef8bf0e0c08418ed74b33120185fd044

  • SHA1

    4c0654f0475f0e001cfbf9bf47caed94ae137af8

  • SHA256

    d8b500427918db815fb5b55eb807c8830192ea1ccd676d4a17155f4d10a1c36e

  • SHA512

    b343f4de6369004adb8a5d042ed272fc8b6680c5013fe6dba98161cfe32c3a518a3c055eb46973d7768874462aa506414e236997e6984706e193e4a7999016ab

Malware Config

Extracted

Family

oski

C2

205.185.120.57

Signatures

  • Oski

    Oski is an infostealer targeting browser data, crypto wallets.

  • Downloads MZ/PE file
  • Loads dropped DLL 3 IoCs
  • Reads user/profile data of web browsers 2 TTPs

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

  • Accesses cryptocurrency files/wallets, possible credential harvesting 2 TTPs
  • Checks installed software on the system 1 TTPs

    Looks up Uninstall key entries in the registry to enumerate software on the system.

  • Suspicious use of SetThreadContext 1 IoCs
  • Enumerates physical storage devices 1 TTPs

    Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.

  • Checks processor information in registry 2 TTPs 1 IoCs

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

  • Kills process with taskkill 1 IoCs
  • Suspicious behavior: EnumeratesProcesses 10 IoCs
  • Suspicious use of AdjustPrivilegeToken 2 IoCs
  • Suspicious use of WriteProcessMemory 21 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe
    "C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe"
    1⤵
    • Suspicious use of SetThreadContext
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:3212
    • C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe
      C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe
      2⤵
        PID:3396
      • C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe
        C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe
        2⤵
          PID:3488
        • C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe
          C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe
          2⤵
          • Loads dropped DLL
          • Checks processor information in registry
          • Suspicious use of WriteProcessMemory
          PID:3456
          • C:\Windows\SysWOW64\cmd.exe
            "C:\Windows\System32\cmd.exe" /c taskkill /pid 3456 & erase C:\Users\Admin\AppData\Local\Temp\ef8bf0e0c08418ed74b33120185fd044.exe & RD /S /Q C:\\ProgramData\\220398869702575\\* & exit
            3⤵
            • Suspicious use of WriteProcessMemory
            PID:3732
            • C:\Windows\SysWOW64\taskkill.exe
              taskkill /pid 3456
              4⤵
              • Kills process with taskkill
              • Suspicious use of AdjustPrivilegeToken
              PID:1380

      Network

      MITRE ATT&CK Matrix ATT&CK v6

      Credential Access

      Credentials in Files

      2
      T1081

      Discovery

      Query Registry

      2
      T1012

      System Information Discovery

      2
      T1082

      Collection

      Data from Local System

      2
      T1005

      Replay Monitor

      Loading Replay Monitor...

      Downloads

      • \ProgramData\mozglue.dll
        MD5

        8f73c08a9660691143661bf7332c3c27

        SHA1

        37fa65dd737c50fda710fdbde89e51374d0c204a

        SHA256

        3fe6b1c54b8cf28f571e0c5d6636b4069a8ab00b4f11dd842cfec00691d0c9cd

        SHA512

        0042ecf9b3571bb5eba2de893e8b2371df18f7c5a589f52ee66e4bfbaa15a5b8b7cc6a155792aaa8988528c27196896d5e82e1751c998bacea0d92395f66ad89

      • \ProgramData\nss3.dll
        MD5

        bfac4e3c5908856ba17d41edcd455a51

        SHA1

        8eec7e888767aa9e4cca8ff246eb2aacb9170428

        SHA256

        e2935b5b28550d47dc971f456d6961f20d1633b4892998750140e0eaa9ae9d78

        SHA512

        2565bab776c4d732ffb1f9b415992a4c65b81bcd644a9a1df1333a269e322925fc1df4f76913463296efd7c88ef194c3056de2f1ca1357d7b5fe5ff0da877a66

      • \ProgramData\sqlite3.dll
        MD5

        e477a96c8f2b18d6b5c27bde49c990bf

        SHA1

        e980c9bf41330d1e5bd04556db4646a0210f7409

        SHA256

        16574f51785b0e2fc29c2c61477eb47bb39f714829999511dc8952b43ab17660

        SHA512

        335a86268e7c0e568b1c30981ec644e6cd332e66f96d2551b58a82515316693c1859d87b4f4b7310cf1ac386cee671580fdd999c3bcb23acf2c2282c01c8798c

      • memory/1380-129-0x0000000000000000-mapping.dmp
      • memory/3212-121-0x0000000005060000-0x000000000507E000-memory.dmp
        Filesize

        120KB

      • memory/3212-120-0x0000000005010000-0x0000000005011000-memory.dmp
        Filesize

        4KB

      • memory/3212-114-0x0000000000760000-0x0000000000761000-memory.dmp
        Filesize

        4KB

      • memory/3212-119-0x0000000005000000-0x0000000005001000-memory.dmp
        Filesize

        4KB

      • memory/3212-118-0x0000000005090000-0x0000000005091000-memory.dmp
        Filesize

        4KB

      • memory/3212-117-0x00000000029F0000-0x00000000029F2000-memory.dmp
        Filesize

        8KB

      • memory/3212-116-0x0000000005510000-0x0000000005511000-memory.dmp
        Filesize

        4KB

      • memory/3456-123-0x000000000040717B-mapping.dmp
      • memory/3456-122-0x0000000000400000-0x0000000000438000-memory.dmp
        Filesize

        224KB

      • memory/3456-124-0x0000000000400000-0x0000000000438000-memory.dmp
        Filesize

        224KB

      • memory/3732-128-0x0000000000000000-mapping.dmp