Analysis
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max time kernel
150s -
max time network
38s -
platform
windows7_x64 -
resource
win7v20210408 -
submitted
21-07-2021 21:12
Static task
static1
Behavioral task
behavioral1
Sample
skin.exe
Resource
win7v20210408
Behavioral task
behavioral2
Sample
skin.exe
Resource
win10v20210408
General
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Target
skin.exe
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Size
21KB
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MD5
0dd3173feb2aad3ff8ea4ec119a88640
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SHA1
a032af45d2222e34f19728207b7411a443eb8f72
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SHA256
a965c7ee5e32a7763ef8e666f12b96699cad180fdd1b8313afaf7177d61d2527
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SHA512
5ddd1a92d8c9fc2b7e611285179af418f1b07dd96ebe0f9879403d2e8dc5b2d0ee4911abfa9c23f57da55e0d17165786b2d4c38d1bc7a2faff1873f0ce807052
Malware Config
Signatures
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Executes dropped EXE 1 IoCs
Processes:
yykymu.exepid process 1572 yykymu.exe -
Processes:
resource yara_rule C:\Windows\yykymu.exe upx C:\Windows\yykymu.exe upx -
Deletes itself 1 IoCs
Processes:
cmd.exepid process 1940 cmd.exe -
Drops file in Windows directory 2 IoCs
Processes:
skin.exedescription ioc process File created C:\Windows\yykymu.exe skin.exe File opened for modification C:\Windows\yykymu.exe skin.exe -
Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.
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Checks processor information in registry 2 TTPs 2 IoCs
Processor information is often read in order to detect sandboxing environments.
Processes:
yykymu.exedescription ioc process Key opened \REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0 yykymu.exe Key value queried \REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\~MHz yykymu.exe -
Suspicious use of AdjustPrivilegeToken 2 IoCs
Processes:
skin.exedescription pid process Token: SeIncBasePriorityPrivilege 364 skin.exe Token: SeIncBasePriorityPrivilege 364 skin.exe -
Suspicious use of WriteProcessMemory 8 IoCs
Processes:
skin.exedescription pid process target process PID 364 wrote to memory of 1940 364 skin.exe cmd.exe PID 364 wrote to memory of 1940 364 skin.exe cmd.exe PID 364 wrote to memory of 1940 364 skin.exe cmd.exe PID 364 wrote to memory of 1940 364 skin.exe cmd.exe PID 364 wrote to memory of 1276 364 skin.exe cmd.exe PID 364 wrote to memory of 1276 364 skin.exe cmd.exe PID 364 wrote to memory of 1276 364 skin.exe cmd.exe PID 364 wrote to memory of 1276 364 skin.exe cmd.exe
Processes
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C:\Users\Admin\AppData\Local\Temp\skin.exe"C:\Users\Admin\AppData\Local\Temp\skin.exe"1⤵
- Drops file in Windows directory
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:364 -
C:\Windows\SysWOW64\cmd.exe"C:\Windows\system32\cmd.exe" /c del C:\Users\Admin\AppData\Local\Temp\skin.exe > nul2⤵
- Deletes itself
PID:1940
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C:\Windows\SysWOW64\cmd.exe"C:\Windows\system32\cmd.exe" /c del C:\Users\Admin\AppData\Local\Temp\skin.exe > nul2⤵PID:1276
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C:\Windows\yykymu.exeC:\Windows\yykymu.exe1⤵
- Executes dropped EXE
- Checks processor information in registry
PID:1572
Network
MITRE ATT&CK Enterprise v6
Replay Monitor
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Downloads
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MD5
0dd3173feb2aad3ff8ea4ec119a88640
SHA1a032af45d2222e34f19728207b7411a443eb8f72
SHA256a965c7ee5e32a7763ef8e666f12b96699cad180fdd1b8313afaf7177d61d2527
SHA5125ddd1a92d8c9fc2b7e611285179af418f1b07dd96ebe0f9879403d2e8dc5b2d0ee4911abfa9c23f57da55e0d17165786b2d4c38d1bc7a2faff1873f0ce807052
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MD5
0dd3173feb2aad3ff8ea4ec119a88640
SHA1a032af45d2222e34f19728207b7411a443eb8f72
SHA256a965c7ee5e32a7763ef8e666f12b96699cad180fdd1b8313afaf7177d61d2527
SHA5125ddd1a92d8c9fc2b7e611285179af418f1b07dd96ebe0f9879403d2e8dc5b2d0ee4911abfa9c23f57da55e0d17165786b2d4c38d1bc7a2faff1873f0ce807052