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

Processes:

resource	yara_rule
\Program Files\Common Files\System\symsrv.dll	floxif

ACProtect 1.3x - 1.4x DLL software 1 IoCs

Detects file using ACProtect software.

Processes:

resource	yara_rule
\Program Files\Common Files\System\symsrv.dll	acprotect

Loads dropped DLL 1 IoCs

Processes:

rnrwBsCuxDulkmr.exe

pid process

2324 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

Processes:

rnrwBsCuxDulkmr.exe

description ioc process

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

pid	process
2324	rnrwBsCuxDulkmr.exe

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

Processes:

resource	yara_rule
\Program Files\Common Files\System\symsrv.dll	upx
behavioral1/memory/2324-3-0x0000000010000000-0x0000000010030000-memory.dmp	upx
behavioral1/memory/2324-31-0x0000000010000000-0x0000000010030000-memory.dmp	upx

Drops file in Program Files directory 1 IoCs

Processes:

rnrwBsCuxDulkmr.exe

description ioc process

File created C:\Program Files\Common Files\System\symsrv.dll rnrwBsCuxDulkmr.exe
Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).

System Information Discovery
T1082

description	ioc	process
File created	C:\Program Files\Common Files\System\symsrv.dll	rnrwBsCuxDulkmr.exe

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

Processes:

rnrwBsCuxDulkmr.exeNOTEPAD.EXE

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

Opens file in notepad (likely ransom note) 1 IoCs
ransomware

Processes:

NOTEPAD.EXE

pid process

2564 NOTEPAD.EXE
Suspicious behavior: EnumeratesProcesses 3 IoCs

Processes:

rnrwBsCuxDulkmr.exe

pid process

2324 rnrwBsCuxDulkmr.exe
2324 rnrwBsCuxDulkmr.exe
2324 rnrwBsCuxDulkmr.exe
Suspicious use of AdjustPrivilegeToken 1 IoCs

Processes:

rnrwBsCuxDulkmr.exe

description pid process

Token: SeDebugPrivilege 2324 rnrwBsCuxDulkmr.exe

pid	process
2564	NOTEPAD.EXE

pid	process
2324	rnrwBsCuxDulkmr.exe
2324	rnrwBsCuxDulkmr.exe
2324	rnrwBsCuxDulkmr.exe

description	pid	process
Token: SeDebugPrivilege	2324	rnrwBsCuxDulkmr.exe

Suspicious use of WriteProcessMemory 4 IoCs

Processes:

rnrwBsCuxDulkmr.exe

description	pid	process	target process
PID 2324 wrote to memory of 2564	2324	rnrwBsCuxDulkmr.exe	NOTEPAD.EXE
PID 2324 wrote to memory of 2564	2324	rnrwBsCuxDulkmr.exe	NOTEPAD.EXE
PID 2324 wrote to memory of 2564	2324	rnrwBsCuxDulkmr.exe	NOTEPAD.EXE
PID 2324 wrote to memory of 2564	2324	rnrwBsCuxDulkmr.exe	NOTEPAD.EXE

C:\Users\Admin\AppData\Local\Temp\rnrwBsCuxDulkmr.exe
"C:\Users\Admin\AppData\Local\Temp\rnrwBsCuxDulkmr.exe"
1⤵
- Loads dropped DLL
- Enumerates connected drives
- Drops file in Program Files directory
- System Location Discovery: System Language Discovery
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:2324
- 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:2564

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

2

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
5f933cb493d179def7da6f69178573b0

SHA1
25f00c520b8f36a6a10c4e2665d9896abf0facca

SHA256
4435adf440a1a26382be7636683630842f1993798d0f6961e56ad75e0d253df7

SHA512
366d478c55c2cf07100693bd91ab5710f80fc75221527d8a53caae8740016e3492e7b3d5a5c95bef4811b5f0a0b2d834bc52408eb88e826c95b9f0155ff81a82

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

Filesize
67KB

MD5
7574cf2c64f35161ab1292e2f532aabf

SHA1
14ba3fa927a06224dfe587014299e834def4644f

SHA256
de055a89de246e629a8694bde18af2b1605e4b9b493c7e4aef669dd67acf5085

SHA512
4db19f2d8d5bc1c7bbb812d3fa9c43b80fa22140b346d2760f090b73aed8a5177edb4bddc647a6ebd5a2db8565be5a1a36a602b0d759e38540d9a584ba5896ab

Download Submit
memory/2324-3-0x0000000010000000-0x0000000010030000-memory.dmp

Filesize
192KB

Download
memory/2324-5-0x00000000002E1000-0x00000000002E2000-memory.dmp

Filesize
4KB

Download
memory/2324-31-0x0000000010000000-0x0000000010030000-memory.dmp

Filesize
192KB

Download
memory/2324-29-0x00000000002E0000-0x000000000040A000-memory.dmp

Filesize
1.2MB

Download

Analysis

Sharing

General

Malware Config

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads