floxif | ed4e3a26d49cfdfce3c734d35bead1aef612614c1ec6ab7ce4110d936ec2e43c

General

Target

rnrwBsCuxDulkmr.exe
Size

268KB
MD5

55d0dadc4feb5873b80d1a61d7a8c622
SHA1

afff011f61f629d240865389298f60465384f468
SHA256

ed4e3a26d49cfdfce3c734d35bead1aef612614c1ec6ab7ce4110d936ec2e43c
SHA512

1f3162c2dbf1bf040549986d256ba36c835bf8ab5aa22536cd50ae31a1c4385f1aac5412d935b2752be039ccdddb302f2e0e03edf192de67aca5a83abe0a2ce1
SSDEEP

6144:n147gBGl86ggtZEvDQ9u7JaSBV+UdvrEFp7hKcR0:nmIGBggtZEvDQwJnBjvrEH7/R0

Score

10^/10

floxif backdoor discovery trojan upx

Malware Config

Signatures

Floxif family
floxif
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
behavioral1/files/0x000c000000023b26-1.dat	floxif

ACProtect 1.3x - 1.4x DLL software 1 IoCs

Detects file using ACProtect software.

resource	yara_rule
behavioral1/files/0x000c000000023b26-1.dat	acprotect

Checks computer location settings 2 TTPs 1 IoCs

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

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000\Control Panel\International\Geo\Nation	rnrwBsCuxDulkmr.exe

Loads dropped DLL 1 IoCs

pid	Process
1208	rnrwBsCuxDulkmr.exe

Enumerates connected drives 3 TTPs 1 IoCs

Attempts to read the root path of hard drives other than the default C: drive.

Query Registry

T1012

Peripheral Device Discovery

T1120

System Information Discovery

T1082

description	ioc	Process
File opened (read-only)	\??\e:	rnrwBsCuxDulkmr.exe

UPX packed file 3 IoCs

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

upx

resource	yara_rule
behavioral1/files/0x000c000000023b26-1.dat	upx
behavioral1/memory/1208-4-0x0000000010000000-0x0000000010030000-memory.dmp	upx
behavioral1/memory/1208-24-0x0000000010000000-0x0000000010030000-memory.dmp	upx

Drops file in Program Files directory 2 IoCs

description	ioc	Process
File created	C:\Program Files\Common Files\System\symsrv.dll	rnrwBsCuxDulkmr.exe
File created	\??\c:\program files\common files\system\symsrv.dll.000	rnrwBsCuxDulkmr.exe

Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).

System Information Discovery
T1082

System Location Discovery: System Language Discovery 1 TTPs 2 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	rnrwBsCuxDulkmr.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	NOTEPAD.EXE

Modifies registry class 1 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-3350944739-639801879-157714471-1000_Classes\Local Settings	rnrwBsCuxDulkmr.exe

Opens file in notepad (likely ransom note) 1 IoCs

ransomware

pid	Process
4540	NOTEPAD.EXE

Suspicious behavior: EnumeratesProcesses 4 IoCs

pid	Process
1208	rnrwBsCuxDulkmr.exe
1208	rnrwBsCuxDulkmr.exe
1208	rnrwBsCuxDulkmr.exe
1208	rnrwBsCuxDulkmr.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	1208	rnrwBsCuxDulkmr.exe

Suspicious use of WriteProcessMemory 3 IoCs

description	pid	Process	procid_target
PID 1208 wrote to memory of 4540	1208	rnrwBsCuxDulkmr.exe	86
PID 1208 wrote to memory of 4540	1208	rnrwBsCuxDulkmr.exe	86
PID 1208 wrote to memory of 4540	1208	rnrwBsCuxDulkmr.exe	86

C:\Users\Admin\AppData\Local\Temp\rnrwBsCuxDulkmr.exe
"C:\Users\Admin\AppData\Local\Temp\rnrwBsCuxDulkmr.exe"
1⤵
- Checks computer location settings
- Loads dropped DLL
- Enumerates connected drives
- Drops file in Program Files directory
- System Location Discovery: System Language Discovery
- Modifies registry class
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:1208
- C:\Windows\SysWOW64\NOTEPAD.EXE
  "C:\Windows\system32\NOTEPAD.EXE" C:\HWID.txt
  2⤵
  - System Location Discovery: System Language Discovery
  - Opens file in notepad (likely ransom note)
  PID:4540

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Peripheral Device Discovery

Query Registry

System Information Discovery

3

T1082

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\HWID.txt

Filesize
271B

MD5
62b821a7d9becd48af855e0aca36c46d

SHA1
ece0fc237d99d906d74cf60526f79ed867b0cf26

SHA256
4a830dfac5e453de7a91070634535340c670f5d7842e47890f6dc78b55e70885

SHA512
33ecd343f1f8004fb9bb4b9acc4c4291365b55565b60a694f55f426ccd86faf22c4ad359d90965f1d8d8780922359d427c5263cd01dbae51493c8b9507eedb01

Download Submit
C:\Program Files\Common Files\System\symsrv.dll

Filesize
67KB

MD5
7574cf2c64f35161ab1292e2f532aabf

SHA1
14ba3fa927a06224dfe587014299e834def4644f

SHA256
de055a89de246e629a8694bde18af2b1605e4b9b493c7e4aef669dd67acf5085

SHA512
4db19f2d8d5bc1c7bbb812d3fa9c43b80fa22140b346d2760f090b73aed8a5177edb4bddc647a6ebd5a2db8565be5a1a36a602b0d759e38540d9a584ba5896ab

Download Submit
memory/1208-4-0x0000000010000000-0x0000000010030000-memory.dmp

Filesize
192KB

Download
memory/1208-6-0x00000000008E1000-0x00000000008E2000-memory.dmp

Filesize
4KB

Download
memory/1208-24-0x0000000010000000-0x0000000010030000-memory.dmp

Filesize
192KB

Download
memory/1208-23-0x00000000008E0000-0x0000000000A0A000-memory.dmp

Filesize
1.2MB

Download

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads