floxif | a20b409e022f9a4e487672ad3b9647e7bd08fe6a6917541298aff1fdb847c62d

General

Target
a20b409e022f9a4e487672ad3b9647e7bd08fe6a6917541298aff1fdb847c62d.dll
Size 123KB
Sample240913-a78jcavhpc
SHA256 a20b409e022f9a4e487672ad3b9647e7bd08fe6a6917541298aff1fdb847c62d
MD5 77d648cae74fc002d1c7e0337b78e6a8
SHA1 56be41bec3784f35946a3f9b78d32764069a75bc
SHA512 5221e519672430e3dee9c079b8f09ba271939071b2f128a9181d49baf636cb582d88c2fba795d4483d31ffa918a770e21a139b8d44f51f136ff5e21987b67a0a
SSDEEP 3072:3C3nVdQ1FJeVk0vLfg6iOZ9czn2lQBV+UdE+rECWp7hKojsv3:cnVdoFUM6iOZ9czLBV+UdvrEFp7hKoje
MD5 SHA1 SHA512 SSDEEP

Score

10^/10

floxif backdoor discovery trojan upx

Malware Config

Signatures

Floxif, Floodfix
Floxif aka FloodFix is a file-changing trojan and backdoor written in C++.
backdoor trojan floxif

Detects Floxif payload 1 IoCs

backdoor

resource	yara_rule
behavioral2/files/0x000800000002347f-1.dat	floxif

ACProtect 1.3x - 1.4x DLL software 1 IoCs

Detects file using ACProtect software.

resource	yara_rule
behavioral2/files/0x000800000002347f-1.dat	acprotect

Loads dropped DLL 1 IoCs

pid	Process
2908	regsvr32.exe

UPX packed file 3 IoCs

Detects executables packed with UPX/modified UPX open source packer.

upx

resource	yara_rule
behavioral2/files/0x000800000002347f-1.dat	upx
behavioral2/memory/2908-4-0x0000000010000000-0x0000000010030000-memory.dmp	upx
behavioral2/memory/2908-7-0x0000000010000000-0x0000000010030000-memory.dmp	upx

Drops file in Program Files directory 1 IoCs

description	ioc	Process
File created	C:\Program Files\Common Files\System\symsrv.dll	regsvr32.exe

System Location Discovery: System Language Discovery 1 TTPs 1 IoCs

Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

discovery

System Language Discovery

T1614.001

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	regsvr32.exe

Modifies registry class 14 IoCs

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{8E14549B-DB61-4309-AFA1-3578E927E935}\InprocServer32\ThreadingModel = "Both"	regsvr32.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node	regsvr32.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{33D9A762-90C8-11d0-BD43-00A0C911CE86}\Instance\{8E14549B-DB61-4309-AFA1-3578E927E935}\CLSID = "{8E14549B-DB61-4309-AFA1-3578E927E935}"	regsvr32.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{8E14549B-DB61-4309-AFA1-3578E927E935}	regsvr32.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{8E14549B-DB61-4309-AFA1-3578E927E935}\InprocServer32	regsvr32.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{8E14549B-DB61-4309-AFA1-3578E927E935}\InprocServer32\ = "C:\\Users\\Admin\\AppData\\Local\\Temp\\a20b409e022f9a4e487672ad3b9647e7bd08fe6a6917541298aff1fdb847c62d.dll"	regsvr32.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{33D9A762-90C8-11d0-BD43-00A0C911CE86}\Instance\{8E14549B-DB61-4309-AFA1-3578E927E935}	regsvr32.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{33D9A762-90C8-11d0-BD43-00A0C911CE86}\Instance\{8E14549B-DB61-4309-AFA1-3578E927E935}\FriendlyName = "virtual-audio-capturer"	regsvr32.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{33D9A762-90C8-11D0-BD43-00A0C911CE86}\Instance\{8E14549B-DB61-4309-AFA1-3578E927E935}	regsvr32.exe
Set value (data)	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{33D9A762-90C8-11d0-BD43-00A0C911CE86}\Instance\{8E14549B-DB61-4309-AFA1-3578E927E935}\FilterData = 02000000000020000100000000000000307069330800000000000000010000000000000000000000307479330000000038000000480000006175647300001000800000aa00389b7100000000000000000000000000000000	regsvr32.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{33D9A762-90C8-11d0-BD43-00A0C911CE86}\Instance	regsvr32.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{8E14549B-DB61-4309-AFA1-3578E927E935}\ = "virtual-audio-capturer"	regsvr32.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID	regsvr32.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{33D9A762-90C8-11D0-BD43-00A0C911CE86}	regsvr32.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	2908	regsvr32.exe

Suspicious use of WriteProcessMemory 3 IoCs

description	pid	Process	procid_target
PID 3788 wrote to memory of 2908	3788	regsvr32.exe	85
PID 3788 wrote to memory of 2908	3788	regsvr32.exe	85
PID 3788 wrote to memory of 2908	3788	regsvr32.exe	85

C:\Windows\system32\regsvr32.exe
regsvr32 /s C:\Users\Admin\AppData\Local\Temp\a20b409e022f9a4e487672ad3b9647e7bd08fe6a6917541298aff1fdb847c62d.dll
1⤵
- Suspicious use of WriteProcessMemory
PID:3788
- C:\Windows\SysWOW64\regsvr32.exe
  /s C:\Users\Admin\AppData\Local\Temp\a20b409e022f9a4e487672ad3b9647e7bd08fe6a6917541298aff1fdb847c62d.dll
  2⤵
  - Loads dropped DLL
  - Drops file in Program Files directory
  - System Location Discovery: System Language Discovery
  - Modifies registry class
  - Suspicious use of AdjustPrivilegeToken
  PID:2908

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

symsrv.dll

Path C:\Program Files\Common Files\System\symsrv.dll
Size 67KB
SHA256 de055a89de246e629a8694bde18af2b1605e4b9b493c7e4aef669dd67acf5085
MD5 7574cf2c64f35161ab1292e2f532aabf
SHA1 14ba3fa927a06224dfe587014299e834def4644f
SHA512 4db19f2d8d5bc1c7bbb812d3fa9c43b80fa22140b346d2760f090b73aed8a5177edb4bddc647a6ebd5a2db8565be5a1a36a602b0d759e38540d9a584ba5896ab
SSDEEP 1536:YjV8y93KQpFQmPLRk7G50zy/riF12jvRyo0hQk7ZL:c8y93KQjy7G55riF1cMo03V
MD5 SHA1 SHA512 SSDEEP

Submit Download

memory/2908-4-0x0000000010000000-0x0000000010030000-memory.dmp

Download

memory/2908-7-0x0000000010000000-0x0000000010030000-memory.dmp