Analysis
-
max time kernel
146s -
max time network
147s -
platform
windows7_x64 -
resource
win7-20240705-en -
resource tags
arch:x64arch:x86image:win7-20240705-enlocale:en-usos:windows7-x64system -
submitted
13/07/2024, 09:53
Static task
static1
Behavioral task
behavioral1
Sample
412f4845d9c0a668fc6d550adf0fcd27_JaffaCakes118.html
Resource
win7-20240705-en
Behavioral task
behavioral2
Sample
412f4845d9c0a668fc6d550adf0fcd27_JaffaCakes118.html
Resource
win10v2004-20240709-en
General
-
Target
412f4845d9c0a668fc6d550adf0fcd27_JaffaCakes118.html
-
Size
52KB
-
MD5
412f4845d9c0a668fc6d550adf0fcd27
-
SHA1
ecadeac322f96495c6164fe0296ba96fec4588aa
-
SHA256
1d8c9adb6b74455351e4a3ee275de8398ce92cbedd7d51dbac8f3c592f5c735b
-
SHA512
03a73ca1b11720d3fcc910c4de6abc894891b684bba27a0fef31ba96e2de175705df96cfaedcb8659baf4c6d5d8e38b5c3e6bebdaa62773eb997ed660212f299
-
SSDEEP
1536:SWnNSxZY7Jmut+Ss+9vBJBQeoE0wb13FKs60gGwIKDS3LNKmWeDuceqa9f+f5:SWnQjQEQGq/Qfs5
Malware Config
Signatures
-
description ioc Process Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\LowRegistry\DontShowMeThisDialogAgain iexplore.exe Set value (str) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main\WindowsSearch\Version = "WS not running" iexplore.exe Set value (int) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\DomainSuggestion\NextUpdateDate = "427026293" iexplore.exe Set value (int) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\TabbedBrowsing\NTPFirstRun = "1" iexplore.exe Set value (data) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\TabbedBrowsing\NewTabPage\DecayDateQueue = 01000000d08c9ddf0115d1118c7a00c04fc297eb0100000082ebb0b9d6f3f0458e93e15bd38f268f000000000200000000001066000000010000200000009ce3873460ce53de70c18b2b71f6e0e648117251639f850c52e04a816d4c6501000000000e8000000002000020000000492fca2eb75a6be611c4d139d524e68fbd5df2fef66e24fe627c4fb4daff256e20000000be027a887316daf8229118b82275446744cb0d3b67007f40c4c4dba1ee466c3140000000996fcb459b6f62fa41a14fa3ede8bcf7eae5a3c9959bcde14ca0702d27b4d660628ac731b9c9f291222b4462f49a8e76613c77951b42da9e73c7d88f86930f2e iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\BrowserEmulation\LowMic iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\IntelliForms iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\LowRegistry iexplore.exe Set value (str) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main\FullScreen = "no" iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Recovery\PendingRecovery iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\GPU iexplore.exe Set value (int) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Recovery\AdminActive\{CB3F1FB1-40FD-11EF-9FC9-7AEB201C29E3} = "0" iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\DomainSuggestion iexplore.exe Set value (data) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\TabbedBrowsing\NewTabPage\MFV = 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 iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\IETld\LowMic iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\LowRegistry\DOMStorage iexplore.exe Set value (str) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main\WindowsSearch\Version = "WS not running" IEXPLORE.EXE Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Recovery\AdminActive iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\TabbedBrowsing iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\TabbedBrowsing\NewTabPage iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\PageSetup iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main IEXPLORE.EXE Set value (int) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Recovery\PendingRecovery\AdminActive = "0" iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Toolbar iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Toolbar\WebBrowser iexplore.exe Set value (int) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main\CompatibilityFlags = "0" iexplore.exe Set value (int) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Recovery\PendingRecovery\AdminActive = "1" iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\SearchScopes iexplore.exe Set value (int) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\SearchScopes\DownloadRetries = "2" iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\InternetRegistry iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Zoom iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main\WindowsSearch iexplore.exe Set value (data) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main\Window_Placement = 2c0000000200000003000000ffffffffffffffffffffffffffffffff2400000024000000aa04000089020000 iexplore.exe Key created \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\Main\WindowsSearch IEXPLORE.EXE Set value (data) \REGISTRY\USER\S-1-5-21-1385883288-3042840365-2734249351-1000\Software\Microsoft\Internet Explorer\TabbedBrowsing\NewTabPage\LastProcessed = 00c71bbb0ad5da01 iexplore.exe -
Suspicious use of FindShellTrayWindow 1 IoCs
pid Process 2352 iexplore.exe -
Suspicious use of SetWindowsHookEx 6 IoCs
pid Process 2352 iexplore.exe 2352 iexplore.exe 1668 IEXPLORE.EXE 1668 IEXPLORE.EXE 1668 IEXPLORE.EXE 1668 IEXPLORE.EXE -
Suspicious use of WriteProcessMemory 4 IoCs
description pid Process procid_target PID 2352 wrote to memory of 1668 2352 iexplore.exe 30 PID 2352 wrote to memory of 1668 2352 iexplore.exe 30 PID 2352 wrote to memory of 1668 2352 iexplore.exe 30 PID 2352 wrote to memory of 1668 2352 iexplore.exe 30
Processes
-
C:\Program Files\Internet Explorer\iexplore.exe"C:\Program Files\Internet Explorer\iexplore.exe" C:\Users\Admin\AppData\Local\Temp\412f4845d9c0a668fc6d550adf0fcd27_JaffaCakes118.html1⤵
- Modifies Internet Explorer settings
- Suspicious use of FindShellTrayWindow
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:2352 -
C:\Program Files (x86)\Internet Explorer\IEXPLORE.EXE"C:\Program Files (x86)\Internet Explorer\IEXPLORE.EXE" SCODEF:2352 CREDAT:275457 /prefetch:22⤵
- Modifies Internet Explorer settings
- Suspicious use of SetWindowsHookEx
PID:1668
-
Network
MITRE ATT&CK Enterprise v15
Replay Monitor
Loading Replay Monitor...
Downloads
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5a39c9bbe5bedfa27c6b637bb4a15eae8
SHA15dea142435fd5857c013b9c1f3d599f304159c1e
SHA256b6614f0b68e8caf757db3d4d023c1b18c66f0d9a015558888a09083e7fc23c72
SHA5129814864d05c24950d5b62afbe9af00abb3663ca9cb7006a299b2dadaa8e93dafe8698fe1da87c96926e19bd5ebe0959354edcb1339c1f66500af3100310304f2
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD508e0b2fbaa1ee5eeb738177f65d30971
SHA1a31909681e332f69125ac5e40e5106d65088e849
SHA256b67554580b82e855af83a1902cf7abea190d0738e834445d4d342843c828f174
SHA5129ac724a10c8d800eb46e73cf3d4485a542b47125ea701128462102992690e628f4edef74f1fc0f3dcc03df72d1f22ad08812a6d49df46ae63e154bf590dd2c11
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD58a5b35a0e575ead4fb1fc2ec06bc94e7
SHA12e0f7755d259e3d699ee166a31daf949dfa5e8f0
SHA2569e2f199bbd0244bdf4db55bbf126670080c02d28e53243b75d8dd764184d9156
SHA5122c2cbd95cabddf8036dde019604c553097cae49a20e05e67e5655e6ac246521cc00881dafb9969cf9073a72f224c5bc961622980b7d0423b7382118c42a1f087
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD596e5728f942f35b63e34ba0de48afc50
SHA1404a8a9c3de7c1ebc1fcd0b3b111802086875222
SHA2568e4a09ef21fd1c97c1a58e0b86e2011e2bcdf5defa7b95de387487942368f85d
SHA512fefe55dd643b9644834f737181b63615d69fe5dbf7471a03a398306501ab3f060a8ed63f513e9ea78e65ae146b74b489eb8d3d455fe6871f767f36a543b15285
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD57f3beea52da9782fffd2d14f9567ff75
SHA10af49e72e6bc4242e88bc98f90dce5cb4b0a87b6
SHA256aa7893094356bc7056fabc940ec857c6c2485968dbee792a975b3a32cd7d6d66
SHA512ce61f1138710ea9489ff034798ef545a1dac11d377fd86ebe4ee76f12ba027436d7ee8eff8cbc00fd959fcd80d0eee2ee700b03a1db328eb06eb36efb3d179cb
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5fbf03867e4c15702193b7fabb8bf6753
SHA1ee6f7ce6a59054266b0314d2c69c8c8af54c3c88
SHA256c90eb2d69d22886cb77610bb727f9df2d86ec9730f44ac76d439c9dbfbe1b85a
SHA512035655ff2004313bffbbd36e87dd3662383cfb184f55c641d501e64ef0d953b7d9a6f01b1ae742d07647782131c837c488dca6a510c8ced0323b4978a4243e7a
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD501ed2dbf0497170b9574dca746e9a0ec
SHA1c08063315e58a0b2719c62ef3228643de587b1bf
SHA2563109cae94797f48d427315b4f9637b250604412f130d7b3e35cdaa82fa9ce6cc
SHA5124f021fa33a2fa4a35b2264dca75487fdd226d136a5d2656f452143e1f966dbf3ffc58515a2030b02b2ad4c265071b1b9671328bebb63a8149d11224a8741da88
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5551660ef74828c87e74e638bd933a4f5
SHA1a9db39e763120136f9713c7408e24fbc6f1c9a06
SHA2563c76c3cb1b0840fc2d123027a82aedd0243a60aee86e958eede36eb7f51ec32c
SHA512ca3411d5e8891fcd13d5fd93382818d4187ff8b3e79ae229ebf254f158040f1bf39bce104d6ce766793252801b53342b164c4de4abb6ec79f8efce6de143a269
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5b27a7959c45d04b4f63c643c6f7189b5
SHA1501d096dbf290b03db0e0a6558d73a29be2a158f
SHA256045ac3add12800b32bff74c6d4b77f981a7a369bdcfa0a8be5dc241c05c9b902
SHA512074ea0153cd623f7d2ba177fe4f2c33bb59c5a9a109446e82c0c5124bd34d3c53f3295f08d4e0b7eb55a54af581bf31afc3eaac19d5945dc60294e7212e03e5a
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5469ffe0b02de99dffe8c09cbb615abd3
SHA152aa38c59d55ba4e55500a97ddca9356e96b8239
SHA256fbf7bde342aa6171ceee2799e53b8bb0beb816237fef6138dc6f5264f35be4e1
SHA5126d546faf1997641d1842fc0a0f3159fab8a34fad619ee3cf003d94b8454a635819e6e923592d96c9cb46c98e65bcd052afe467666b8e7221d9ec8b5b85c6e4cf
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD58cfa9acf2cb72c3ed74a09eb6b0d9fc0
SHA1d4a442ad6eb39cc7e7d08c9db722992a603ab8a2
SHA256ed06e335bab305a19886c35b667be3f13e4dccf54062b941370d96478dfe9594
SHA51285e32584b40d7ccfd79c0f2230d058f031133b2e904a05c805d45176640331a539d9b0531c86b56e6795eef464556f236f7fdce880f29528c552e0b5d3284fb1
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5a1687637a3b88ddd420b6197d298f656
SHA124fb27503552b19f601766b6093da1b1a9eb9167
SHA256682593d84e3351a1b5766722e21317d89dbcfe3d0cc6f0800a233faa3064e3b4
SHA512ef046ad8dbe099cbddc5f14f2277dcca51403175281b8ee0e789307cfa44c56a860abca95347605c07f777f0944b20b82cda3f76c1b1e7fbbf3814fd2a4ce2d0
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD58c2982e3662cc051213622eb66b54dd3
SHA19f98ea80651689d9a6c945729d2a7754059d869a
SHA2564d5f84789bde62200ee7e0da5e160da3730b53a9a35da2bbb6e2f6b34de58eaa
SHA512e9f5b95707af68ad391a5e739ef4e5075055ce8885b4ac13e88be21968cfdd850a19f8851a786861b4eb58d24a5810146de95d9c0085301569ed8822a1ebaecd
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5686b87dd6445b96ff0bc6ad37b6113ca
SHA1fce9332920b983d2e9de0884b47098be575f7134
SHA256270652caed786712ce1bb036d963bea06925243bb78bee4e37426c73a8f7561f
SHA512080ee79e60c8ff261edd4e880230aa62ce174980e1a3e6e9e1c048f06ee57c725f24b6aa47fae556ca762e4d4560a430eb4c892545ba507fb1b7e4a9a7a3a6d5
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5f3e317c90711f34032fbc5e1a8862c58
SHA149c6a5b6efa40df8a69564041170163a462df18f
SHA25602a1db61ad5e263bef4b4c7158bd3a55ec3cf623db43b3ab12905ec4bbd45d2c
SHA512529392758c12cd748309cb8bfe04fad55a0de44987df33ada4636c29df060c8f72d54379a108a4ee1039bfd50f2d0678fac42b7c04bdf933320a1cfe31fdd330
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD55b425c9c680cd79ae2520669c7707f1b
SHA1bfe80d6fcd0440f1d86a1a45cf7782fc32c93373
SHA256e698d4aaee854425f71275a25ced48bb117ae7c43765c0ce9bae43653416e869
SHA512132e63266dafe1c80efeec1f423de8dae231720a21c7c472662181f409a6cf451f94ac69d39169c3973ab322a8507a88acc695e989cb0be5acd8320ae93f0699
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD573ff02dca748e767e354b7f5d95aa6b0
SHA1b1688bb9564acc9a97814c937c57fee341c26529
SHA256d680406c7265d9f34a9a006b08f917ea4da077d7572a6e5227a17a307f45016a
SHA512f689a3b9915cd81e0843b4e573b7c23b4674c83fbde9291b9b75dfd14477b37a070f95aac1422a5e483cf40f40fda76bf9ad94036225932ab78de3225d47eb52
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5e72913f1c5c00a68481cd6b5e0d666c4
SHA13f2a7aaaa8aef34a433062aea0ecfdd494bd5383
SHA25614164860722ba8f594aebacad1d7894458f778892d98edaddd283cf82c751363
SHA512cf0b6c517098e43b5f0627ff8d8dd35841d7686884d34b8c4cb79ed711a09babf6a8c4b3b94efbfa41e2d4fe92ba371cacf2f240c16655843a41d25db7366f55
-
C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015
Filesize342B
MD5d76b04963db6913e1c3753d123e31001
SHA14a10c2a43eb41079ee360f897bba9a20cf87fca3
SHA256dde60b559b74411a273f14701abc1e5be5f3050f3dd178b9669eba97befa1454
SHA512656d2bac516e2f6007222c05ac9c7fad43006495b03c6113958e1021836e28f59b9ce60d79dfb08abd9530ba59930296a44a067f8d2a26b9e31016070fb4f6f5
-
Filesize
70KB
MD549aebf8cbd62d92ac215b2923fb1b9f5
SHA11723be06719828dda65ad804298d0431f6aff976
SHA256b33efcb95235b98b48508e019afa4b7655e80cf071defabd8b2123fc8b29307f
SHA512bf86116b015fb56709516d686e168e7c9c68365136231cc51d0b6542ae95323a71d2c7acec84aad7dcecc2e410843f6d82a0a6d51b9acfc721a9c84fdd877b5b
-
Filesize
181KB
MD54ea6026cf93ec6338144661bf1202cd1
SHA1a1dec9044f750ad887935a01430bf49322fbdcb7
SHA2568efbc21559ef8b1bcf526800d8070baad42474ce7198e26fa771dbb41a76b1d8
SHA5126c7e0980e39aacf4c3689802353f464a08cd17753bd210ee997e5f2a455deb4f287a9ef74d84579dbde49bc96213cd2b8b247723919c412ea980aa6e6bfe218b