117b0078905f0929a5da0b24e20c76bbaa99151f56789c63b4498143c2261926

General

Target

FishLocker.exe
Size

218KB
MD5

85d90010fed526eef947c440629b82dd
SHA1

1df270d02c9ea53f180130e7a219b40146cfca10
SHA256

117b0078905f0929a5da0b24e20c76bbaa99151f56789c63b4498143c2261926
SHA512

1455958c884f15e03531b1e836269fc6b2bab60e1a4b360e1206568ca7aabee0f55599eab4d11889359818c859d8d37d725bd90109165ca7626d045a81e75be7

Score

10^/10

discovery evasion exploit persistence

Malware Config

Signatures

Modifies WinLogon for persistence 2 TTPs 1 IoCs
persistence

Winlogon Helper DLL
T1004

Modify Registry
T1112

Processes:

FishLocker.exe

description ioc process

Set value (str) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "empty" FishLocker.exe
Disables Task Manager via registry modification
evasion
Possible privilege escalation attempt 4 IoCs
exploit

Processes:

icacls.exetakeown.exeicacls.exetakeown.exe

pid process

616 icacls.exe
1792 takeown.exe
1692 icacls.exe
1196 takeown.exe
Modifies file permissions 1 TTPs 4 IoCs
discovery

File Permissions Modification
T1222

Processes:

takeown.exeicacls.exetakeown.exeicacls.exe

pid process

1792 takeown.exe
1692 icacls.exe
1196 takeown.exe
616 icacls.exe
Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.

System Information Discovery
T1082
Program crash 1 IoCs

Processes:

WerFault.exe

pid pid_target process target process

300 1636 WerFault.exe FishLocker.exe
Suspicious behavior: EnumeratesProcesses 6 IoCs

Processes:

FishLocker.exeWerFault.exe

pid process

1636 FishLocker.exe
300 WerFault.exe
300 WerFault.exe
300 WerFault.exe
300 WerFault.exe
300 WerFault.exe
Suspicious behavior: GetForegroundWindowSpam 1 IoCs

Processes:

WerFault.exe

pid process

300 WerFault.exe

description	ioc	process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "empty"	FishLocker.exe

pid	process
616	icacls.exe
1792	takeown.exe
1692	icacls.exe
1196	takeown.exe

pid	process
1792	takeown.exe
1692	icacls.exe
1196	takeown.exe
616	icacls.exe

pid	pid_target	process	target process
300	1636	WerFault.exe	FishLocker.exe

pid	process
1636	FishLocker.exe
300	WerFault.exe
300	WerFault.exe
300	WerFault.exe
300	WerFault.exe
300	WerFault.exe

pid	process
300	WerFault.exe

Suspicious use of AdjustPrivilegeToken 5 IoCs

Processes:

FishLocker.exetakeown.exetakeown.exeWerFault.exe

description	pid	process
Token: SeDebugPrivilege	1636	FishLocker.exe
Token: SeDebugPrivilege	1636	FishLocker.exe
Token: SeTakeOwnershipPrivilege	1792	takeown.exe
Token: SeTakeOwnershipPrivilege	1196	takeown.exe
Token: SeDebugPrivilege	300	WerFault.exe

Suspicious use of WriteProcessMemory 18 IoCs

Processes:

FishLocker.execmd.exe

description	pid	process	target process
PID 1636 wrote to memory of 1964	1636	FishLocker.exe	cmd.exe
PID 1636 wrote to memory of 1964	1636	FishLocker.exe	cmd.exe
PID 1636 wrote to memory of 1964	1636	FishLocker.exe	cmd.exe
PID 1964 wrote to memory of 1792	1964	cmd.exe	takeown.exe
PID 1964 wrote to memory of 1792	1964	cmd.exe	takeown.exe
PID 1964 wrote to memory of 1792	1964	cmd.exe	takeown.exe
PID 1964 wrote to memory of 1692	1964	cmd.exe	icacls.exe
PID 1964 wrote to memory of 1692	1964	cmd.exe	icacls.exe
PID 1964 wrote to memory of 1692	1964	cmd.exe	icacls.exe
PID 1964 wrote to memory of 1196	1964	cmd.exe	takeown.exe
PID 1964 wrote to memory of 1196	1964	cmd.exe	takeown.exe
PID 1964 wrote to memory of 1196	1964	cmd.exe	takeown.exe
PID 1964 wrote to memory of 616	1964	cmd.exe	icacls.exe
PID 1964 wrote to memory of 616	1964	cmd.exe	icacls.exe
PID 1964 wrote to memory of 616	1964	cmd.exe	icacls.exe
PID 1636 wrote to memory of 300	1636	FishLocker.exe	WerFault.exe
PID 1636 wrote to memory of 300	1636	FishLocker.exe	WerFault.exe
PID 1636 wrote to memory of 300	1636	FishLocker.exe	WerFault.exe

C:\Users\Admin\AppData\Local\Temp\FishLocker.exe
"C:\Users\Admin\AppData\Local\Temp\FishLocker.exe"
1⤵
- Modifies WinLogon for persistence
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:1636

C:\Windows\System32\cmd.exe
"C:\Windows\System32\cmd.exe" /k color 47 && takeown /f C:\Windows\System32 && icacls C:\Windows\System32 /grant %username%:F && takeown /f C:\Windows\System32\drivers && icacls C:\Windows\System32\drivers /grant %username%:F && Exit
2⤵
- Suspicious use of WriteProcessMemory
PID:1964

C:\Windows\system32\takeown.exe
takeown /f C:\Windows\System32
3⤵
- Possible privilege escalation attempt
- Modifies file permissions
- Suspicious use of AdjustPrivilegeToken
PID:1792

C:\Windows\system32\icacls.exe
icacls C:\Windows\System32 /grant Admin:F
3⤵
- Possible privilege escalation attempt
- Modifies file permissions
PID:1692

C:\Windows\system32\takeown.exe
takeown /f C:\Windows\System32\drivers
3⤵
- Possible privilege escalation attempt
- Modifies file permissions
- Suspicious use of AdjustPrivilegeToken
PID:1196

C:\Windows\system32\icacls.exe
icacls C:\Windows\System32\drivers /grant Admin:F
3⤵
- Possible privilege escalation attempt
- Modifies file permissions
PID:616

C:\Windows\system32\WerFault.exe
C:\Windows\system32\WerFault.exe -u -p 1636 -s 976
2⤵
- Program crash
- Suspicious behavior: EnumeratesProcesses
- Suspicious behavior: GetForegroundWindowSpam
- Suspicious use of AdjustPrivilegeToken
PID:300

MITRE ATT&CK Matrix ATT&CK v6

Initial Access

Execution

Persistence

Winlogon Helper DLL

1

T1004

Privilege Escalation

Defense Evasion

Modify Registry

1

T1112

File Permissions Modification

1

T1222

Credential Access

Discovery

System Information Discovery

1

T1082

Lateral Movement

Collection

Exfiltration

Command and Control

Impact

Replay Monitor

Loading Replay Monitor...

Downloads

memory/300-69-0x0000000000000000-mapping.dmp

Download
memory/300-70-0x000007FEFBFF1000-0x000007FEFBFF3000-memory.dmp

Filesize
8KB

Download
memory/300-71-0x0000000000360000-0x0000000000361000-memory.dmp

Filesize
4KB

Download
memory/616-68-0x0000000000000000-mapping.dmp

Download
memory/1196-67-0x0000000000000000-mapping.dmp

Download
memory/1636-59-0x0000000000870000-0x0000000000871000-memory.dmp

Filesize
4KB

Download
memory/1636-61-0x000000001B310000-0x000000001B312000-memory.dmp

Filesize
8KB

Download
memory/1636-65-0x000000001B312000-0x000000001B313000-memory.dmp

Filesize
4KB

Download
memory/1636-66-0x000000001B317000-0x000000001B336000-memory.dmp

Filesize
124KB

Download
memory/1692-64-0x0000000000000000-mapping.dmp

Download
memory/1792-63-0x0000000000000000-mapping.dmp

Download
memory/1964-62-0x0000000000000000-mapping.dmp

Download

Analysis

Sharing