buer | e4817740d78a5543811272a0b6de0a226594c84b2801926b53ced825f68bd529

Analysis

max time kernel
1762s
max time network
1767s
platform
windows7_x64
resource
win7
submitted
14-07-2020 20:52

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General

Target

Doc-Print.exe
Size

368KB
MD5

fcc9314bc996fa04721aa469e1d982df
SHA1

c306f42bd091c86328651e30c15ac49a7ebb02c4
SHA256

e4817740d78a5543811272a0b6de0a226594c84b2801926b53ced825f68bd529
SHA512

fac82d815108b111b3a63063e757c2d5ed367e3a94dbe3dc3af252f8c1968aead07df32405f3f16012b13b203f264d764666b49ac192daa98334a3c3be32c0f3

Score

10^/10

buer metasploit backdoor loader persistence trojan

Malware Config

Extracted

Family

buer

https://162.244.81.87/

http://162.244.81.87:8080/

Extracted

Family

metasploit

Version

windows/download_exec

http://31.14.40.55:80/YRDm

Attributes

headers User-Agent: Mozilla/5.0 (compatible; MSIE 9.0; qdesk 2.4.1263.203; Windows NT 6.1; WOW64; Trident/5.0)

Signatures

Buer
Buer is a new modular loader first seen in August 2019.
loader buer
MetaSploit
Detected malicious payload which is part of the Metasploit Framework, likely generated with msfvenom or similar.
trojan backdoor metasploit

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\\201d0b90eb65c4e04a98\\gennt.exe\""	gennt.exe

Buer Loader 2 IoCs

Detects Buer loader in memory or disk.

resource	yara_rule
behavioral1/memory/284-0-0x0000000000330000-0x000000000033C000-memory.dmp	buer
behavioral1/memory/1852-6-0x0000000000280000-0x000000000028C000-memory.dmp	buer

Executes dropped EXE 1 IoCs

pid	Process
1852	gennt.exe

Deletes itself 1 IoCs

pid	Process
1852	gennt.exe

Loads dropped DLL 3 IoCs

pid	Process
284	Doc-Print.exe
284	Doc-Print.exe
1468	regsvr32.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)	\??\K:	gennt.exe
File opened (read-only)	\??\M:	gennt.exe
File opened (read-only)	\??\Y:	gennt.exe
File opened (read-only)	\??\O:	gennt.exe
File opened (read-only)	\??\P:	gennt.exe
File opened (read-only)	\??\X:	gennt.exe
File opened (read-only)	\??\A:	gennt.exe
File opened (read-only)	\??\G:	gennt.exe
File opened (read-only)	\??\I:	gennt.exe
File opened (read-only)	\??\L:	gennt.exe
File opened (read-only)	\??\F:	gennt.exe
File opened (read-only)	\??\Q:	gennt.exe
File opened (read-only)	\??\T:	gennt.exe
File opened (read-only)	\??\W:	gennt.exe
File opened (read-only)	\??\N:	gennt.exe
File opened (read-only)	\??\R:	gennt.exe
File opened (read-only)	\??\S:	gennt.exe
File opened (read-only)	\??\U:	gennt.exe
File opened (read-only)	\??\B:	gennt.exe
File opened (read-only)	\??\E:	gennt.exe
File opened (read-only)	\??\H:	gennt.exe
File opened (read-only)	\??\J:	gennt.exe
File opened (read-only)	\??\V:	gennt.exe
File opened (read-only)	\??\Z:	gennt.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

pid	pid_target	Process	procid_target
1912	1868	WerFault.exe	27

Suspicious behavior: EnumeratesProcesses 6 IoCs

pid	Process
1912	WerFault.exe
1912	WerFault.exe
1912	WerFault.exe
1912	WerFault.exe
1852	gennt.exe
1852	gennt.exe

Suspicious behavior: GetForegroundWindowSpam 1 IoCs

pid	Process
1912	WerFault.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	1912	WerFault.exe

Suspicious use of SetWindowsHookEx 4 IoCs

pid	Process
284	Doc-Print.exe
284	Doc-Print.exe
1852	gennt.exe
1852	gennt.exe

Suspicious use of WriteProcessMemory 30 IoCs

description	pid	Process	procid_target
PID 284 wrote to memory of 1852	284	Doc-Print.exe	26
PID 284 wrote to memory of 1852	284	Doc-Print.exe	26
PID 284 wrote to memory of 1852	284	Doc-Print.exe	26
PID 284 wrote to memory of 1852	284	Doc-Print.exe	26
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1852 wrote to memory of 1868	1852	gennt.exe	27
PID 1868 wrote to memory of 1912	1868	secinit.exe	28
PID 1868 wrote to memory of 1912	1868	secinit.exe	28
PID 1868 wrote to memory of 1912	1868	secinit.exe	28
PID 1868 wrote to memory of 1912	1868	secinit.exe	28
PID 1852 wrote to memory of 1824	1852	gennt.exe	29
PID 1852 wrote to memory of 1824	1852	gennt.exe	29
PID 1852 wrote to memory of 1824	1852	gennt.exe	29
PID 1852 wrote to memory of 1824	1852	gennt.exe	29
PID 1852 wrote to memory of 1468	1852	gennt.exe	33
PID 1852 wrote to memory of 1468	1852	gennt.exe	33
PID 1852 wrote to memory of 1468	1852	gennt.exe	33
PID 1852 wrote to memory of 1468	1852	gennt.exe	33
PID 1852 wrote to memory of 1468	1852	gennt.exe	33
PID 1852 wrote to memory of 1468	1852	gennt.exe	33
PID 1852 wrote to memory of 1468	1852	gennt.exe	33

C:\Users\Admin\AppData\Local\Temp\Doc-Print.exe
"C:\Users\Admin\AppData\Local\Temp\Doc-Print.exe"
1⤵
- Loads dropped DLL
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:284
- C:\ProgramData\201d0b90eb65c4e04a98\gennt.exe
  C:\ProgramData\201d0b90eb65c4e04a98\gennt.exe "C:\Users\Admin\AppData\Local\Temp\Doc-Print.exe" ensgJJ
  2⤵
  - Modifies WinLogon for persistence
  - Executes dropped EXE
  - Deletes itself
  - Enumerates connected drives
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of SetWindowsHookEx
  - Suspicious use of WriteProcessMemory
  PID:1852
- - C:\Windows\SysWOW64\secinit.exe
    C:\ProgramData\201d0b90eb65c4e04a98\gennt.exe
    3⤵
    - Suspicious use of WriteProcessMemory
    PID:1868
  - - C:\Windows\SysWOW64\WerFault.exe
      C:\Windows\SysWOW64\WerFault.exe -u -p 1868 -s 196
      4⤵
      Program crash
      Suspicious behavior: EnumeratesProcesses
      Suspicious behavior: GetForegroundWindowSpam
      Suspicious use of AdjustPrivilegeToken
      PID:1912
- - C:\Windows\SysWOW64\cmd.exe
    "C:\Windows\System32\cmd.exe" powershell.exe -Command "& {Add-MpPreference -ExclusionPath C:\ProgramData\201d0b90eb65c4e04a98}"
    3⤵
    PID:1824
- - C:\Windows\SysWOW64\regsvr32.exe
    "C:\Windows\System32\regsvr32.exe" "C:\ProgramData\201d0b90eb65c4e04a98\vemyonacsi.dll"
    3⤵
    - Loads dropped DLL
    PID:1468

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Winlogon Helper DLL

T1004

Privilege Escalation

Defense Evasion

Modify Registry

T1112

Credential Access

Discovery

Peripheral Device Discovery

T1120

Query Registry

T1012

System Information Discovery

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

memory/284-0-0x0000000000330000-0x000000000033C000-memory.dmp

Filesize
48KB

Download
memory/1468-19-0x00000000008E0000-0x00000000008E1000-memory.dmp

Filesize
4KB

Download
memory/1468-18-0x000000006BAC0000-0x000000006BACB000-memory.dmp

Filesize
44KB

Download
memory/1468-17-0x00000000001A0000-0x00000000001A9000-memory.dmp

Filesize
36KB

Download
memory/1852-6-0x0000000000280000-0x000000000028C000-memory.dmp

Filesize
48KB

Download
memory/1912-12-0x00000000025C0000-0x00000000025D1000-memory.dmp

Filesize
68KB

Download
memory/1912-9-0x0000000001F00000-0x0000000001F11000-memory.dmp

Filesize
68KB

Download