Analysis

  • max time kernel
    121s
  • max time network
    123s
  • platform
    windows7_x64
  • resource
    win7v20201028
  • submitted
    06-04-2021 12:39

General

  • Target

    791d39e806357e832c5aa1043ebdfe95c90ffe41f20376ad5ea955b049c5dac7.exe

  • Size

    684KB

  • MD5

    b53c91938416807d1ee5a408c5b2a636

  • SHA1

    2bd54114bccd24abf158ee1b5ae1e77a238f4bc1

  • SHA256

    791d39e806357e832c5aa1043ebdfe95c90ffe41f20376ad5ea955b049c5dac7

  • SHA512

    855ffa525e36e9406d8c4ee9c148effe994c1e513ea498757ef91918d93c2c9a33ffdce457b31754c8cf65577caa012320ccd450bdc82cac6963b0dbed110dac

Malware Config

Extracted

Family

oski

C2

http://45.85.90.220

Signatures

  • Oski

    Oski is an infostealer targeting browser data, crypto wallets.

  • Downloads MZ/PE file
  • Loads dropped DLL 5 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 use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of WriteProcessMemory 18 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\791d39e806357e832c5aa1043ebdfe95c90ffe41f20376ad5ea955b049c5dac7.exe
    "C:\Users\Admin\AppData\Local\Temp\791d39e806357e832c5aa1043ebdfe95c90ffe41f20376ad5ea955b049c5dac7.exe"
    1⤵
    • Suspicious use of SetThreadContext
    • Suspicious use of WriteProcessMemory
    PID:532
    • C:\Users\Admin\AppData\Local\Temp\791d39e806357e832c5aa1043ebdfe95c90ffe41f20376ad5ea955b049c5dac7.exe
      "C:\Users\Admin\AppData\Local\Temp\791d39e806357e832c5aa1043ebdfe95c90ffe41f20376ad5ea955b049c5dac7.exe"
      2⤵
      • Loads dropped DLL
      • Checks processor information in registry
      • Suspicious use of WriteProcessMemory
      PID:1132
      • C:\Windows\SysWOW64\cmd.exe
        "C:\Windows\System32\cmd.exe" /c taskkill /pid 1132 & erase C:\Users\Admin\AppData\Local\Temp\791d39e806357e832c5aa1043ebdfe95c90ffe41f20376' & RD /S /Q C:\\ProgramData\\453344522693753\\* & exit
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:808
        • C:\Windows\SysWOW64\taskkill.exe
          taskkill /pid 1132
          4⤵
          • Kills process with taskkill
          • Suspicious use of AdjustPrivilegeToken
          PID:1104

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\msvcp140.dll
    MD5

    109f0f02fd37c84bfc7508d4227d7ed5

    SHA1

    ef7420141bb15ac334d3964082361a460bfdb975

    SHA256

    334e69ac9367f708ce601a6f490ff227d6c20636da5222f148b25831d22e13d4

    SHA512

    46eb62b65817365c249b48863d894b4669e20fcb3992e747cd5c9fdd57968e1b2cf7418d1c9340a89865eadda362b8db51947eb4427412eb83b35994f932fd39

  • \ProgramData\nss3.dll
    MD5

    bfac4e3c5908856ba17d41edcd455a51

    SHA1

    8eec7e888767aa9e4cca8ff246eb2aacb9170428

    SHA256

    e2935b5b28550d47dc971f456d6961f20d1633b4892998750140e0eaa9ae9d78

    SHA512

    2565bab776c4d732ffb1f9b415992a4c65b81bcd644a9a1df1333a269e322925fc1df4f76913463296efd7c88ef194c3056de2f1ca1357d7b5fe5ff0da877a66

  • \ProgramData\sqlite3.dll
    MD5

    e477a96c8f2b18d6b5c27bde49c990bf

    SHA1

    e980c9bf41330d1e5bd04556db4646a0210f7409

    SHA256

    16574f51785b0e2fc29c2c61477eb47bb39f714829999511dc8952b43ab17660

    SHA512

    335a86268e7c0e568b1c30981ec644e6cd332e66f96d2551b58a82515316693c1859d87b4f4b7310cf1ac386cee671580fdd999c3bcb23acf2c2282c01c8798c

  • \ProgramData\vcruntime140.dll
    MD5

    7587bf9cb4147022cd5681b015183046

    SHA1

    f2106306a8f6f0da5afb7fc765cfa0757ad5a628

    SHA256

    c40bb03199a2054dabfc7a8e01d6098e91de7193619effbd0f142a7bf031c14d

    SHA512

    0b63e4979846ceba1b1ed8470432ea6aa18cca66b5f5322d17b14bc0dfa4b2ee09ca300a016e16a01db5123e4e022820698f46d9bad1078bd24675b4b181e91f

  • memory/532-7-0x0000000000BA0000-0x0000000000C00000-memory.dmp
    Filesize

    384KB

  • memory/532-2-0x00000000740C0000-0x00000000747AE000-memory.dmp
    Filesize

    6.9MB

  • memory/532-6-0x0000000004C70000-0x0000000004C71000-memory.dmp
    Filesize

    4KB

  • memory/532-5-0x00000000008A0000-0x00000000008A9000-memory.dmp
    Filesize

    36KB

  • memory/532-3-0x0000000000C00000-0x0000000000C01000-memory.dmp
    Filesize

    4KB

  • memory/808-18-0x0000000000000000-mapping.dmp
  • memory/1104-19-0x0000000000000000-mapping.dmp
  • memory/1132-9-0x000000000040717B-mapping.dmp
  • memory/1132-10-0x0000000075C61000-0x0000000075C63000-memory.dmp
    Filesize

    8KB

  • memory/1132-11-0x0000000000400000-0x0000000000438000-memory.dmp
    Filesize

    224KB

  • memory/1132-8-0x0000000000400000-0x0000000000438000-memory.dmp
    Filesize

    224KB

  • memory/1740-12-0x000007FEF7040000-0x000007FEF72BA000-memory.dmp
    Filesize

    2.5MB