Analysis

  • max time kernel
    143s
  • max time network
    148s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20230220-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20230220-enlocale:en-usos:windows10-2004-x64system
  • submitted
    15/03/2023, 00:43

General

  • Target

    service_updated.exe

  • Size

    26KB

  • MD5

    41129b2de89d99f0bd5e1ad1f6440eef

  • SHA1

    48ed7f4ed02069d40eca3e1398cda78df33d94e7

  • SHA256

    6573a46dcc3f3695b69d5f395bc71515b34890ddc4a73b017afab37421512542

  • SHA512

    93c22380c3ae75a1cc087716b94665626b6e0418dc4e1eb65afee536282571ed3a28607a3cf4b7ff1fbbd9ad0cda70349d556c4b0b9a17981357100c6a0d7eca

  • SSDEEP

    384:sJJo2hYvWMUMGYZacX1weJiPRQMFWsXrMTW4g1CwL1CyDb+/cG7myv+pQ6ZD0m3H:lEHqSeJiJVXrM41v1C8bpCT+Zgm3HtN

Malware Config

Extracted

Family

asyncrat

Version

1.0.7

Botnet

Default

Mutex

DcRatMutex_qwqdanchun

Attributes
  • delay

    10

  • install

    true

  • install_file

    csrss.exe

  • install_folder

    %AppData%

  • pastebin_config

    https://pastebin.com/raw/3Z9zi18j

aes.plain

Signatures

  • AsyncRat

    AsyncRAT is designed to remotely monitor and control other computers written in C#.

  • Async RAT payload 6 IoCs
  • Downloads MZ/PE file
  • Sets file to hidden 1 TTPs 1 IoCs

    Modifies file attributes to stop it showing in Explorer etc.

  • Checks computer location settings 2 TTPs 2 IoCs

    Looks up country code configured in the registry, likely geofence.

  • Executes dropped EXE 4 IoCs
  • Legitimate hosting services abused for malware hosting/C2 1 TTPs
  • Enumerates physical storage devices 1 TTPs

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

  • Creates scheduled task(s) 1 TTPs 1 IoCs

    Schtasks is often used by malware for persistence or to perform post-infection execution.

  • Delays execution with timeout.exe 1 IoCs
  • Modifies registry class 1 IoCs
  • Suspicious behavior: EnumeratesProcesses 24 IoCs
  • Suspicious use of AdjustPrivilegeToken 44 IoCs
  • Suspicious use of WriteProcessMemory 19 IoCs
  • Uses Task Scheduler COM API 1 TTPs

    The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.

  • Views/modifies file attributes 1 TTPs 1 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\service_updated.exe
    "C:\Users\Admin\AppData\Local\Temp\service_updated.exe"
    1⤵
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:820
    • C:\Windows\system32\attrib.exe
      "C:\Windows\system32\attrib.exe" +s +h C:\Users\Admin\AppData\Local\Temp\tmp6DD7.exe
      2⤵
      • Sets file to hidden
      • Views/modifies file attributes
      PID:3672
    • C:\Users\Admin\AppData\Local\Temp\tmp6DD7.exe
      "C:\Users\Admin\AppData\Local\Temp\tmp6DD7.exe"
      2⤵
      • Checks computer location settings
      • Executes dropped EXE
      • Modifies registry class
      • Suspicious use of WriteProcessMemory
      PID:2904
      • C:\Users\Admin\AppData\Local\Temp\csrss.exe
        "C:\Users\Admin\AppData\Local\Temp\csrss.exe"
        3⤵
        • Checks computer location settings
        • Executes dropped EXE
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        • Suspicious use of WriteProcessMemory
        PID:2548
        • C:\Windows\System32\cmd.exe
          "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "csrss" /tr '"C:\Users\Admin\AppData\Roaming\csrss.exe"' & exit
          4⤵
          • Suspicious use of WriteProcessMemory
          PID:3772
          • C:\Windows\system32\schtasks.exe
            schtasks /create /f /sc onlogon /rl highest /tn "csrss" /tr '"C:\Users\Admin\AppData\Roaming\csrss.exe"'
            5⤵
            • Creates scheduled task(s)
            PID:2008
        • C:\Windows\system32\cmd.exe
          C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmpC1FD.tmp.bat""
          4⤵
          • Suspicious use of WriteProcessMemory
          PID:2476
          • C:\Windows\system32\timeout.exe
            timeout 3
            5⤵
            • Delays execution with timeout.exe
            PID:4460
          • C:\Users\Admin\AppData\Roaming\csrss.exe
            "C:\Users\Admin\AppData\Roaming\csrss.exe"
            5⤵
            • Executes dropped EXE
            • Suspicious use of AdjustPrivilegeToken
            PID:4192
      • C:\Users\Admin\AppData\Local\Temp\Extreme Injector v3.exe
        "C:\Users\Admin\AppData\Local\Temp\Extreme Injector v3.exe"
        3⤵
        • Executes dropped EXE
        • Suspicious use of AdjustPrivilegeToken
        PID:4628

Network

        MITRE ATT&CK Enterprise v6

        Replay Monitor

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        Downloads

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

          Filesize

          425B

          MD5

          fff5cbccb6b31b40f834b8f4778a779a

          SHA1

          899ed0377e89f1ed434cfeecc5bc0163ebdf0454

          SHA256

          b8f7e4ed81764db56b9c09050f68c5a26af78d8a5e2443e75e0e1aa7cd2ccd76

          SHA512

          1a188a14c667bc31d2651b220aa762be9cce4a75713217846fbe472a307c7bbc6e3c27617f75f489902a534d9184648d204d03ee956ac57b11aa90551248b8f9

        • C:\Users\Admin\AppData\Local\Temp\Extreme Injector v3.exe

          Filesize

          1.9MB

          MD5

          ec801a7d4b72a288ec6c207bb9ff0131

          SHA1

          32eec2ae1f9e201516fa7fcdc16c4928f7997561

          SHA256

          b65f40618f584303ca0bcf9b5f88c233cc4237699c0c4bf40ba8facbe8195a46

          SHA512

          a07dd5e8241de73ce65ff8d74acef4942b85fc45cf6a7baafd3c0f9d330b08e7412f2023ba667e99b40e732a65e8fb4389f7fe73c7b6256ca71e63afe46cdcac

        • C:\Users\Admin\AppData\Local\Temp\Extreme Injector v3.exe

          Filesize

          1.9MB

          MD5

          ec801a7d4b72a288ec6c207bb9ff0131

          SHA1

          32eec2ae1f9e201516fa7fcdc16c4928f7997561

          SHA256

          b65f40618f584303ca0bcf9b5f88c233cc4237699c0c4bf40ba8facbe8195a46

          SHA512

          a07dd5e8241de73ce65ff8d74acef4942b85fc45cf6a7baafd3c0f9d330b08e7412f2023ba667e99b40e732a65e8fb4389f7fe73c7b6256ca71e63afe46cdcac

        • C:\Users\Admin\AppData\Local\Temp\Extreme Injector v3.exe

          Filesize

          1.9MB

          MD5

          ec801a7d4b72a288ec6c207bb9ff0131

          SHA1

          32eec2ae1f9e201516fa7fcdc16c4928f7997561

          SHA256

          b65f40618f584303ca0bcf9b5f88c233cc4237699c0c4bf40ba8facbe8195a46

          SHA512

          a07dd5e8241de73ce65ff8d74acef4942b85fc45cf6a7baafd3c0f9d330b08e7412f2023ba667e99b40e732a65e8fb4389f7fe73c7b6256ca71e63afe46cdcac

        • C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_pjhsb0sk.vqd.ps1

          Filesize

          60B

          MD5

          d17fe0a3f47be24a6453e9ef58c94641

          SHA1

          6ab83620379fc69f80c0242105ddffd7d98d5d9d

          SHA256

          96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

          SHA512

          5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

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

          Filesize

          63KB

          MD5

          4e8ed7a82d6919108934eaa3fcd3ed9f

          SHA1

          f74a1c9fc02c8374ec0ee68438ae309f1f61ff41

          SHA256

          c933e7ccae64ffe87abb6f685c4d82ba2de7c9ff56523136e42d56b82b48b364

          SHA512

          2fc905d288a820d08d30b5ba64989406a89a2694af191e900bdde1e55c42ddce66cb5de9f562f8018c115029e5b210dc7b51204c2dccb73d561f5bbd996dfdad

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

          Filesize

          63KB

          MD5

          4e8ed7a82d6919108934eaa3fcd3ed9f

          SHA1

          f74a1c9fc02c8374ec0ee68438ae309f1f61ff41

          SHA256

          c933e7ccae64ffe87abb6f685c4d82ba2de7c9ff56523136e42d56b82b48b364

          SHA512

          2fc905d288a820d08d30b5ba64989406a89a2694af191e900bdde1e55c42ddce66cb5de9f562f8018c115029e5b210dc7b51204c2dccb73d561f5bbd996dfdad

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

          Filesize

          63KB

          MD5

          4e8ed7a82d6919108934eaa3fcd3ed9f

          SHA1

          f74a1c9fc02c8374ec0ee68438ae309f1f61ff41

          SHA256

          c933e7ccae64ffe87abb6f685c4d82ba2de7c9ff56523136e42d56b82b48b364

          SHA512

          2fc905d288a820d08d30b5ba64989406a89a2694af191e900bdde1e55c42ddce66cb5de9f562f8018c115029e5b210dc7b51204c2dccb73d561f5bbd996dfdad

        • C:\Users\Admin\AppData\Local\Temp\tmp6DD7.exe

          Filesize

          2.3MB

          MD5

          83a24ea1847f5cbb5508785abb5126ea

          SHA1

          63930e7171d1fc94fd4ec745392b3a1136cb0496

          SHA256

          246b30f2dc863cc247d9ad8bff17e1ec92f2282810f47f42634c0bb7883ba268

          SHA512

          fb6fbeb92bf4fee54f46e4dd75703cc85ebec3e57594fd7cb14874c096c2783ad896c863ba34c594f368d5c16df6a264e50dbb06d674c565d426dd2ddfe3890e

        • C:\Users\Admin\AppData\Local\Temp\tmp6DD7.exe

          Filesize

          2.3MB

          MD5

          83a24ea1847f5cbb5508785abb5126ea

          SHA1

          63930e7171d1fc94fd4ec745392b3a1136cb0496

          SHA256

          246b30f2dc863cc247d9ad8bff17e1ec92f2282810f47f42634c0bb7883ba268

          SHA512

          fb6fbeb92bf4fee54f46e4dd75703cc85ebec3e57594fd7cb14874c096c2783ad896c863ba34c594f368d5c16df6a264e50dbb06d674c565d426dd2ddfe3890e

        • C:\Users\Admin\AppData\Local\Temp\tmpC1FD.tmp.bat

          Filesize

          149B

          MD5

          9844dbcd75df1529186eee44640fa766

          SHA1

          d882d1ca7277fd862ba986f1fc1cf108a75befba

          SHA256

          ec46866731f7a578c32a9d8bb70e1a33b25cdd8c65f412672196192b8e3b2339

          SHA512

          529eb729c3a0d0a3dc281faba6447bf81db7d87b08e9458c96dce16851cfecb8c0621d13c35c1054198e8c7d0819396956554154c991091e426183736d1b3544

        • C:\Users\Admin\AppData\Roaming\csrss.exe

          Filesize

          63KB

          MD5

          4e8ed7a82d6919108934eaa3fcd3ed9f

          SHA1

          f74a1c9fc02c8374ec0ee68438ae309f1f61ff41

          SHA256

          c933e7ccae64ffe87abb6f685c4d82ba2de7c9ff56523136e42d56b82b48b364

          SHA512

          2fc905d288a820d08d30b5ba64989406a89a2694af191e900bdde1e55c42ddce66cb5de9f562f8018c115029e5b210dc7b51204c2dccb73d561f5bbd996dfdad

        • C:\Users\Admin\AppData\Roaming\csrss.exe

          Filesize

          63KB

          MD5

          4e8ed7a82d6919108934eaa3fcd3ed9f

          SHA1

          f74a1c9fc02c8374ec0ee68438ae309f1f61ff41

          SHA256

          c933e7ccae64ffe87abb6f685c4d82ba2de7c9ff56523136e42d56b82b48b364

          SHA512

          2fc905d288a820d08d30b5ba64989406a89a2694af191e900bdde1e55c42ddce66cb5de9f562f8018c115029e5b210dc7b51204c2dccb73d561f5bbd996dfdad

        • memory/820-133-0x0000000000BA0000-0x0000000000BAC000-memory.dmp

          Filesize

          48KB

        • memory/820-144-0x000000001B6A0000-0x000000001B6C2000-memory.dmp

          Filesize

          136KB

        • memory/820-143-0x000000001B760000-0x000000001B770000-memory.dmp

          Filesize

          64KB

        • memory/2548-229-0x0000000000DF0000-0x0000000000E06000-memory.dmp

          Filesize

          88KB

        • memory/2904-149-0x0000000000400000-0x000000000064E000-memory.dmp

          Filesize

          2.3MB

        • memory/4628-293-0x000000001B640000-0x000000001B650000-memory.dmp

          Filesize

          64KB

        • memory/4628-294-0x000000001B640000-0x000000001B650000-memory.dmp

          Filesize

          64KB

        • memory/4628-291-0x000000001EA10000-0x000000001EA4C000-memory.dmp

          Filesize

          240KB

        • memory/4628-290-0x000000001B670000-0x000000001B682000-memory.dmp

          Filesize

          72KB

        • memory/4628-289-0x000000001B640000-0x000000001B650000-memory.dmp

          Filesize

          64KB

        • memory/4628-288-0x0000000000750000-0x0000000000936000-memory.dmp

          Filesize

          1.9MB