buer | cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd

General

Target

cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe
Size

103KB
MD5

35380d263bbcd4aaa5d158d10ba0f558
SHA1

80c4fabb2412d5482f8c76cf1683eb52d75dfd21
SHA256

cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd
SHA512

7278884e121c16d1a023ac8fa865155b6bb910cdce3a647f869c4aee7f3c14b19f8ecefd931ab725ea66e814d40f33def871a42c03bcc26aad7c7fa918b8e2e3

Score

10^/10

buer loader persistence

Malware Config

Extracted

Family

buer

C2

https://mesoplano.com/

https://banusle.top/

Signatures

Buer
Buer is a new modular loader first seen in August 2019.
loader buer

Modifies WinLogon for persistence 2 TTPs 1 IoCs

persistence

Winlogon Helper DLL

T1004

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, \"C:\\ProgramData\\bed843753aab4cfea285\\gennt.exe\""	gennt.exe

Buer Loader 2 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral1/memory/1916-59-0x0000000000250000-0x000000000025C000-memory.dmp	buer
behavioral1/memory/544-64-0x0000000000250000-0x000000000025C000-memory.dmp	buer

Executes dropped EXE 1 IoCs

pid	Process
544	gennt.exe

Deletes itself 1 IoCs

pid	Process
544	gennt.exe

Loads dropped DLL 2 IoCs

pid	Process
1916	cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe
1916	cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe

Enumerates connected drives 3 TTPs 24 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)	\??\S:	gennt.exe
File opened (read-only)	\??\T:	gennt.exe
File opened (read-only)	\??\Y:	gennt.exe
File opened (read-only)	\??\L:	gennt.exe
File opened (read-only)	\??\Q:	gennt.exe
File opened (read-only)	\??\N:	gennt.exe
File opened (read-only)	\??\X:	gennt.exe
File opened (read-only)	\??\B:	gennt.exe
File opened (read-only)	\??\K:	gennt.exe
File opened (read-only)	\??\G:	gennt.exe
File opened (read-only)	\??\H:	gennt.exe
File opened (read-only)	\??\J:	gennt.exe
File opened (read-only)	\??\M:	gennt.exe
File opened (read-only)	\??\P:	gennt.exe
File opened (read-only)	\??\R:	gennt.exe
File opened (read-only)	\??\A:	gennt.exe
File opened (read-only)	\??\F:	gennt.exe
File opened (read-only)	\??\Z:	gennt.exe
File opened (read-only)	\??\V:	gennt.exe
File opened (read-only)	\??\W:	gennt.exe
File opened (read-only)	\??\O:	gennt.exe
File opened (read-only)	\??\U:	gennt.exe
File opened (read-only)	\??\E:	gennt.exe
File opened (read-only)	\??\I:	gennt.exe

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

System Information Discovery
T1082

Suspicious behavior: EnumeratesProcesses 1 IoCs

pid	Process
544	gennt.exe

Suspicious use of WriteProcessMemory 12 IoCs

description	pid	Process	procid_target
PID 1916 wrote to memory of 544	1916	cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe	27
PID 1916 wrote to memory of 544	1916	cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe	27
PID 1916 wrote to memory of 544	1916	cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe	27
PID 1916 wrote to memory of 544	1916	cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe	27
PID 544 wrote to memory of 776	544	gennt.exe	28
PID 544 wrote to memory of 776	544	gennt.exe	28
PID 544 wrote to memory of 776	544	gennt.exe	28
PID 544 wrote to memory of 776	544	gennt.exe	28
PID 544 wrote to memory of 436	544	gennt.exe	31
PID 544 wrote to memory of 436	544	gennt.exe	31
PID 544 wrote to memory of 436	544	gennt.exe	31
PID 544 wrote to memory of 436	544	gennt.exe	31

C:\Users\Admin\AppData\Local\Temp\cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe
"C:\Users\Admin\AppData\Local\Temp\cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe"
1⤵
- Loads dropped DLL
- Suspicious use of WriteProcessMemory
PID:1916
- C:\ProgramData\bed843753aab4cfea285\gennt.exe
  C:\ProgramData\bed843753aab4cfea285\gennt.exe "C:\Users\Admin\AppData\Local\Temp\cda685d0e85b2f28c00d145da358edc3748357786455965af86a3b0b292051fd.exe" ensgJJ
  2⤵
  - Modifies WinLogon for persistence
  - Executes dropped EXE
  - Deletes itself
  - Enumerates connected drives
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of WriteProcessMemory
  PID:544
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\bed843753aab4cfea285\gennt.exe
    3⤵
    PID:776
- - C:\Windows\SysWOW64\cmd.exe
    "C:\Windows\System32\cmd.exe" powershell.exe -Command "& {Add-MpPreference -ExclusionPath C:\ProgramData\bed843753aab4cfea285}"
    3⤵
    PID:436

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Winlogon Helper DLL

1

T1004

Privilege Escalation

Defense Evasion

Modify Registry

1

T1112

Credential Access

Discovery

Peripheral Device Discovery

Query Registry

System Information Discovery

2

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

memory/544-63-0x0000000000220000-0x0000000000221000-memory.dmp

Filesize
4KB

Download
memory/544-62-0x0000000000400000-0x000000000041D000-memory.dmp

Filesize
116KB

Download
memory/544-64-0x0000000000250000-0x000000000025C000-memory.dmp

Filesize
48KB

Download
memory/1916-54-0x0000000075F21000-0x0000000075F23000-memory.dmp

Filesize
8KB

Download
memory/1916-58-0x0000000000400000-0x000000000041D000-memory.dmp

Filesize
116KB

Download
memory/1916-59-0x0000000000250000-0x000000000025C000-memory.dmp

Filesize
48KB

Download

Analysis

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