Analysis
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max time kernel
150s -
max time network
122s -
platform
windows7_x64 -
resource
win7-20240708-en -
resource tags
arch:x64arch:x86image:win7-20240708-enlocale:en-usos:windows7-x64system -
submitted
21-07-2024 15:03
Static task
static1
Behavioral task
behavioral1
Sample
23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe
Resource
win7-20240708-en
Behavioral task
behavioral2
Sample
23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe
Resource
win10v2004-20240709-en
General
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Target
23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe
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Size
384KB
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MD5
5ac0f050f93f86e69026faea1fbb4450
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SHA1
9709774fde9ec740ad6fed8ed79903296ca9d571
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SHA256
23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2
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SHA512
b554487c4e26a85ec5179cdcc1d25b5bc494e8821a8899fbbf868c3cf41f70cc72db107613b3f6655d3ab70f4db94cce2589066bb354b1ed955098d3911b844d
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SSDEEP
6144:f5yaXtrA/WSo1rl3ALrlHQpn0BwK3SBDmhYfFQC:fTX6WSofcZ+KCIGD
Malware Config
Extracted
C:\RyukReadMe.txt
ryuk
14hVKm7Ft2rxDBFTNkkRC3kGstMGp2A4hk
Signatures
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Ryuk
Ransomware distributed via existing botnets, often Trickbot or Emotet.
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Deletes itself 1 IoCs
Processes:
CMfln.exepid process 2772 CMfln.exe -
Drops startup file 1 IoCs
Processes:
taskhost.exedescription ioc process File opened for modification C:\Users\Admin\AppData\Roaming\Microsoft\Word\STARTUP\RyukReadMe.txt taskhost.exe -
Executes dropped EXE 1 IoCs
Processes:
CMfln.exepid process 2772 CMfln.exe -
Loads dropped DLL 1 IoCs
Processes:
23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exepid process 2672 23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe -
Adds Run key to start application 2 TTPs 1 IoCs
Processes:
reg.exedescription ioc process Set value (str) \REGISTRY\USER\S-1-5-21-1506706701-1246725540-2219210854-1000\Software\Microsoft\Windows\CurrentVersion\Run\svchos = "C:\\users\\Public\\CMfln.exe" reg.exe -
Drops file in Program Files directory 64 IoCs
Processes:
taskhost.exedescription ioc process File opened for modification C:\Program Files (x86)\Microsoft Office\MEDIA\CAGCAT10\J0285926.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\MEDIA\OFFICE14\BULLETS\BD14692_.GIF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\Groove\ToolData\groove.net\GrooveForms4\FormsViewFrame.html taskhost.exe File opened for modification C:\Program Files\VideoLAN\VLC\locale\oc\LC_MESSAGES\vlc.mo taskhost.exe File opened for modification C:\Program Files (x86)\Google\CrashReports\RyukReadMe.txt taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\J0099168.JPG taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\NA00433_.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\MEDIA\CAGCAT10\J0149481.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\PUBWIZ\LETTHEAD.XML taskhost.exe File opened for modification C:\Program Files\DVD Maker\Shared\DvdStyles\BabyBoy\BabyBoyScenesBackground.wmv taskhost.exe File opened for modification C:\Program Files\DVD Maker\Shared\DvdStyles\Performance\Notes_loop.wmv taskhost.exe File opened for modification C:\Program Files\Java\jdk1.7.0_80\jre\lib\zi\Pacific\Niue taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\J0341448.JPG taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Templates\1033\Access\Part\Contacts.accdt taskhost.exe File opened for modification C:\Program Files\DVD Maker\Shared\DvdStyles\Vignette\15x15dot.png taskhost.exe File opened for modification C:\Program Files\Java\jdk1.7.0_80\jre\lib\cmm\GRAY.pf taskhost.exe File opened for modification C:\Program Files\Java\jre7\lib\cmm\CIEXYZ.pf taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\J0107528.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\WB02229_.GIF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\PUBWIZ\LETTHEAD.DPV taskhost.exe File opened for modification C:\Program Files\Java\jre7\lib\zi\Asia\Seoul taskhost.exe File opened for modification C:\Program Files (x86)\Adobe\Reader 9.0\Resource\TypeSupport\Unicode\Mappings\Mac\ROMANIAN.TXT taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\NA01680_.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\MEDIA\CAGCAT10\J0199727.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\J0240157.WMF taskhost.exe File opened for modification C:\Program Files\DVD Maker\Shared\DvdStyles\ResizingPanels\Panel_Mask.wmv taskhost.exe File opened for modification C:\Program Files\Microsoft Games\Mahjong\fr-FR\RyukReadMe.txt taskhost.exe File opened for modification C:\Program Files (x86)\Common Files\microsoft shared\OFFICE14\Office Setup Controller\InfoPath.en-us\InfoPathMUI.XML taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\BL00148_.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\Groove\ToolData\groove.net\GrooveForms\FormsHomePage.html taskhost.exe File opened for modification C:\Program Files\DVD Maker\Shared\DvdStyles\Shatter\NavigationUp_ButtonGraphic.png taskhost.exe File opened for modification C:\Program Files\Java\jdk1.7.0_80\jre\lib\zi\America\Managua taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\AG00011_.GIF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\DD01166_.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\Groove\ToolData\groove.net\GrooveDocumentReview\ActiveTabImage.jpg taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\Groove\ToolData\groove.net\GrooveForms4\FormsStyles\Adobe.css taskhost.exe File opened for modification C:\Program Files (x86)\Common Files\System\Ole DB\es-ES\sqlxmlx.rll.mui taskhost.exe File opened for modification C:\Program Files (x86)\Common Files\microsoft shared\Smart Tag\MSTAG.TLB taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\J0105912.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\PH02756U.BMP taskhost.exe File opened for modification C:\Program Files\Java\jdk1.7.0_80\lib\missioncontrol\plugins\org.eclipse.core.net.nl_ja_4.4.0.v20140623020002.jar taskhost.exe File opened for modification C:\Program Files\Java\jdk1.7.0_80\lib\visualvm\platform\update_tracking\org-netbeans-swing-tabcontrol.xml taskhost.exe File opened for modification C:\Program Files (x86)\Adobe\Reader 9.0\Reader\IDTemplates\ENU\RyukReadMe.txt taskhost.exe File opened for modification C:\Program Files (x86)\Common Files\microsoft shared\THEMES14\NETWORK\THMBNAIL.PNG taskhost.exe File opened for modification C:\Program Files\7-Zip\Lang\ro.txt taskhost.exe File opened for modification C:\Program Files (x86)\Internet Explorer\fr-FR\RyukReadMe.txt taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\1033\CollectSignatures_Init.xsn taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\Groove\ToolBMPs\MessageHistoryIconImages.jpg taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\OutlookAutoDiscover\YAHOO.COM.AU.XML taskhost.exe File opened for modification C:\Program Files\7-Zip\Lang\ta.txt taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\J0105360.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\J0107182.WMF taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\CLIPART\PUB60COR\NA00330_.WMF taskhost.exe File opened for modification C:\Program Files\Java\jdk1.7.0_80\jre\lib\zi\Europe\Madrid taskhost.exe File opened for modification C:\Program Files\Java\jdk1.7.0_80\lib\missioncontrol\plugins\org.eclipse.equinox.p2.directorywatcher.nl_zh_4.4.0.v20140623020002.jar taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\1033\MSPUB.DEV_K_COL.HXK taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\Groove\Sounds\Places\ALARM.WAV taskhost.exe File opened for modification C:\Program Files (x86)\Microsoft Office\Office14\1033\PUBSPAPR\PDIR35B.GIF taskhost.exe File opened for modification C:\Program Files\Internet Explorer\es-ES\RyukReadMe.txt taskhost.exe File opened for modification C:\Program Files\Java\jdk1.7.0_80\lib\missioncontrol\plugins\org.eclipse.ui.themes_1.0.1.v20140819-1717\images\winXPBluTSFrame.png taskhost.exe File opened for modification C:\Program Files\Microsoft Games\Purble Place\es-ES\RyukReadMe.txt taskhost.exe File opened for modification C:\Program Files\VideoLAN\VLC\locale\mai\RyukReadMe.txt taskhost.exe File opened for modification C:\Program Files\DVD Maker\Shared\DvdStyles\rectangle_widescreen_Thumbnail.bmp taskhost.exe File opened for modification C:\Program Files\DVD Maker\Shared\DvdStyles\Stacking\RyukReadMe.txt taskhost.exe -
Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).
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Suspicious behavior: EnumeratesProcesses 1 IoCs
Processes:
CMfln.exepid process 2772 CMfln.exe -
Suspicious use of AdjustPrivilegeToken 1 IoCs
Processes:
CMfln.exedescription pid process Token: SeDebugPrivilege 2772 CMfln.exe -
Suspicious use of WriteProcessMemory 14 IoCs
Processes:
23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exeCMfln.execmd.exedescription pid process target process PID 2672 wrote to memory of 2772 2672 23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe CMfln.exe PID 2672 wrote to memory of 2772 2672 23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe CMfln.exe PID 2672 wrote to memory of 2772 2672 23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe CMfln.exe PID 2672 wrote to memory of 2772 2672 23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe CMfln.exe PID 2772 wrote to memory of 2532 2772 CMfln.exe cmd.exe PID 2772 wrote to memory of 2532 2772 CMfln.exe cmd.exe PID 2772 wrote to memory of 2532 2772 CMfln.exe cmd.exe PID 2772 wrote to memory of 1104 2772 CMfln.exe taskhost.exe PID 2532 wrote to memory of 2996 2532 cmd.exe reg.exe PID 2532 wrote to memory of 2996 2532 cmd.exe reg.exe PID 2532 wrote to memory of 2996 2532 cmd.exe reg.exe PID 2772 wrote to memory of 1168 2772 CMfln.exe Dwm.exe PID 2772 wrote to memory of 864 2772 CMfln.exe DllHost.exe PID 2772 wrote to memory of 2712 2772 CMfln.exe DllHost.exe
Processes
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C:\Windows\system32\taskhost.exe"taskhost.exe"1⤵
- Drops startup file
- Drops file in Program Files directory
PID:1104
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C:\Windows\system32\Dwm.exe"C:\Windows\system32\Dwm.exe"1⤵PID:1168
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C:\Windows\system32\DllHost.exeC:\Windows\system32\DllHost.exe /Processid:{3EB3C877-1F16-487C-9050-104DBCD66683}1⤵PID:864
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C:\Users\Admin\AppData\Local\Temp\23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe"C:\Users\Admin\AppData\Local\Temp\23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe"1⤵
- Loads dropped DLL
- Suspicious use of WriteProcessMemory
PID:2672 -
C:\users\Public\CMfln.exe"C:\users\Public\CMfln.exe" C:\Users\Admin\AppData\Local\Temp\23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.exe2⤵
- Deletes itself
- Executes dropped EXE
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:2772 -
C:\Windows\System32\cmd.exe"C:\Windows\System32\cmd.exe" /C REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run" /v "svchos" /t REG_SZ /d "C:\users\Public\CMfln.exe" /f3⤵
- Suspicious use of WriteProcessMemory
PID:2532 -
C:\Windows\system32\reg.exeREG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run" /v "svchos" /t REG_SZ /d "C:\users\Public\CMfln.exe" /f4⤵
- Adds Run key to start application
PID:2996
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C:\Windows\explorer.exe"C:\Windows\explorer.exe"1⤵PID:3032
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C:\Windows\system32\DllHost.exeC:\Windows\system32\DllHost.exe /Processid:{AB8902B4-09CA-4BB6-B78D-A8F59079A8D5}1⤵PID:2712
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C:\Windows\system32\NOTEPAD.EXE"C:\Windows\system32\NOTEPAD.EXE" F:\RyukReadMe.txt1⤵PID:4724
Network
MITRE ATT&CK Enterprise v15
Replay Monitor
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Downloads
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Filesize
804B
MD5cd99cba6153cbc0b14b7a849e4d0180f
SHA1375961866404a705916cbc6cd4915de7d9778923
SHA25674c43a177917b1d57ea2eaf6212ccf3b9012b4d68bc45284349443eed0bf5ee2
SHA5120c9f250c0e2ec9736b072a9807b6c3bec4b670ab2f511e65cf5d79e9a8c9a209eb91736ce2765b52b6d94a57c6aa1c16bb08e16727660699b70608439c8b7cda
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Filesize
170KB
MD531bd0f224e7e74eee2847f43aae23974
SHA192e331e1e8ad30538f38dd7ba31386afafa14a58
SHA2568b0a5fb13309623c3518473551cb1f55d38d8450129d4a3c16b476f7b2867d7d
SHA512a13f05a12b084ef425f542ff4be824bbccb5dbdfe085af8b7e19d81a6bcba4b8c1debcc38f6b57bc9265a4db21eed70852ece8cc62b3ef14c47fca3035a55249