Trojan.GenericKD.4166976_cc753ddc77

Dynamic Analysis

Payload

Behaviour	Description
WormAutorun	A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Trojan's file once a user opens a drive's folder in Windows Explorer.

Process activity

The Trojan creates the following process(es):

%original file name%.exe:3360
stub.exe:3580

The Trojan injects its code into the following process(es):

dllhost.exe:2876
svchost.exe:160

Mutexes

The following mutexes were created/opened:No objects were found.

File activity

The process %original file name%.exe:3360 makes changes in the file system.

The Trojan creates and/or writes to the following file(s):

C:\Users\"%CurrentUserName%"\AppData\Local\Temp\stub.exe (4744 bytes)

The process dllhost.exe:2876 makes changes in the file system.

The Trojan creates and/or writes to the following file(s):

C:\Windows\System32\COM Surrogate (33 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\GAB0Soyqjnm.dat (308 bytes)

Registry activity

The process %original file name%.exe:3360 makes changes in the system registry.

The Trojan creates and/or sets the following values in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"AutoDetect" = "1"
"UNCAsIntranet" = "0"

The Trojan deletes the following value(s) in system registry:

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"ProxyBypass"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"ProxyBypass"
"IntranetName"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName"

The process dllhost.exe:2876 makes changes in the system registry.

The Trojan creates and/or sets the following values in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"AutoDetect" = "1"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASMANCS]
"ConsoleTracingMask" = "4294901760"

[HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components\{1U272725-I227-YIYP-GC78-RN76A51W5201}]
"StubPath" = "C:\Windows\system32\COM Surrogate restart"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"UNCAsIntranet" = "0"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASMANCS]
"MaxFileSize" = "1048576"

[HKCU\Software\GAB0Soyqjnm]
"ServerName" = "C:\Windows\system32\COM Surrogate"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Wpad]
"WpadLastNetwork" = "{E549E976-C5F2-4E77-819D-55BC9B7C25BC}"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASAPI32]
"MaxFileSize" = "1048576"
"FileDirectory" = "%windir%\tracing"
"ConsoleTracingMask" = "4294901760"

[HKCU\Software\Microsoft\Windows\CurrentVersion/run]
"setup" = "setup"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASMANCS]
"EnableFileTracing" = "0"

[HKCU\Software\GAB0Soyqjnm]
"ServerStarted" = "19/01/2017 11:37:28"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASMANCS]
"FileTracingMask" = "4294901760"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"SavedLegacySettings" = "46 00 00 00 3C 00 00 00 09 00 00 00 00 00 00 00"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASMANCS]
"FileDirectory" = "%windir%\tracing"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASAPI32]
"FileTracingMask" = "4294901760"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASMANCS]
"EnableConsoleTracing" = "0"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASAPI32]
"EnableFileTracing" = "0"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"DefaultConnectionSettings" = "46 00 00 00 0C 00 00 00 09 00 00 00 00 00 00 00"

[HKLM\SOFTWARE\Microsoft\Tracing\dllhost_RASAPI32]
"EnableConsoleTracing" = "0"

Proxy settings are disabled:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

To automatically run itself each time Windows is booted, the Trojan adds the following link to its file to the system registry autorun key:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Java" = "C:\Windows\system32\COM Surrogate"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
"Java" = "C:\Windows\system32\COM Surrogate"

The Trojan deletes the following value(s) in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"ProxyBypass"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"ProxyBypass"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyOverride"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyServer"
"AutoConfigURL"

The process stub.exe:3580 makes changes in the system registry.

The Trojan creates and/or sets the following values in system registry:

[HKCU\Software\XtremeRAT]
"Mutex" = "GAB0Soyqjnm"

Dropped PE files

MD5	File path
43bf064d936d05c58ea5f87d9f08d2d8	c:\Users\"%CurrentUserName%"\AppData\Local\Temp\stub.exe
43bf064d936d05c58ea5f87d9f08d2d8	c:\Windows\System32\COM Surrogate

HOSTS file anomalies

No changes have been detected.

Rootkit activity

No anomalies have been detected.

Propagation

A worm can spread via removable drives. It writes its executable and creates "autorun.inf" scripts on all removable drives. The autorun script will execute the Trojan's file once a user opens a drive's folder in Windows Explorer.

Removals

Remove it with Ad-Aware

1. Click (here) to download and install Ad-Aware Free Antivirus.
2. Update the definition files.
3. Run a full scan of your computer.

Manual removal*

1. Terminate malicious process(es) (How to End a Process With the Task Manager):

   %original file name%.exe:3360
   stub.exe:3580
   

2. Delete the original Trojan file.
   
3. Delete or disinfect the following files created/modified by the Trojan:

   C:\Users\"%CurrentUserName%"\AppData\Local\Temp\stub.exe (4744 bytes)
   C:\Windows\System32\COM Surrogate (33 bytes)
   C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\GAB0Soyqjnm.dat (308 bytes)

4. Delete the following value(s) in the autorun key (How to Work with System Registry):

   [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
   "Java" = "C:\Windows\system32\COM Surrogate"
   
   [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   "Java" = "C:\Windows\system32\COM Surrogate"

5. Clean the Temporary Internet Files folder, which may contain infected files (How to clean Temporary Internet Files folder).
   
6. Find and delete all copies of the worm's file together with "autorun.inf" scripts on removable drives.
   
7. Reboot the computer.
   

*Manual removal may cause unexpected system behaviour and should be performed at your own risk.

Static Analysis

VersionInfo

Company Name:
Product Name: Explorer.exe
Product Version: 1.0.0.0
Legal Copyright: Copyright (c) 2017
Legal Trademarks:
Original Filename: Explorer.exe.exe
Internal Name: Explorer.exe.exe
File Version: 1.0.0.0
File Description: Explorer.exe
Comments:
Language: English (United States)

Company Name: Product Name: Explorer.exeProduct Version: 1.0.0.0Legal Copyright: Copyright (c) 2017Legal Trademarks: Original Filename: Explorer.exe.exeInternal Name: Explorer.exe.exeFile Version: 1.0.0.0File Description: Explorer.exeComments: Language: English (United States)

PE Sections

Name	Virtual Address	Virtual Size	Raw Size	Entropy	Section MD5
.text	8192	572144	572416	4.0741	2a54b95e29eeb711b694330bc30be63b
.rsrc	581632	1484	1536	2.84898	612d04a9b616d3ced64b4f0eaeefb4e0
.reloc	589824	12	512	0.070639	1f525cab2409333b868f23dcf1400509

Dropped from:

Downloaded by:

Similar by SSDeep:

Similar by Lavasoft Polymorphic Checker:

Network Activity

URLs

URL	IP
svrt.zapto.org	191.54.205.240
dns.msftncsi.com	131.107.255.255

IDS verdicts (Suricata alerts: Emerging Threats ET ruleset)

Traffic

Map

The Trojan connects to the servers at the folowing location(s):

Strings from Dumps

svchost.exe_160:

.text

.text

`.data

`.data

.rsrc

.rsrc

@.reloc

@.reloc

msvcrt.dll

msvcrt.dll

API-MS-Win-Core-ProcessThreads-L1-1-0.dll

API-MS-Win-Core-ProcessThreads-L1-1-0.dll

KERNEL32.dll

KERNEL32.dll

NTDLL.DLL

NTDLL.DLL

API-MS-Win-Security-Base-L1-1-0.dll

API-MS-Win-Security-Base-L1-1-0.dll

API-MS-WIN-Service-Core-L1-1-0.dll

API-MS-WIN-Service-Core-L1-1-0.dll

API-MS-WIN-Service-winsvc-L1-1-0.dll

API-MS-WIN-Service-winsvc-L1-1-0.dll

RPCRT4.dll

RPCRT4.dll

ole32.dll

ole32.dll

ntdll.dll

ntdll.dll

_amsg_exit

_amsg_exit

RegCloseKey

RegCloseKey

RegOpenKeyExW

RegOpenKeyExW

GetProcessHeap

GetProcessHeap

svchost.pdb

svchost.pdb

version="5.1.0.0"

version="5.1.0.0"

name="Microsoft.Windows.Services.SvcHost"

name="Microsoft.Windows.Services.SvcHost"

Host Process for Windows Services

Host Process for Windows Services

Software\Microsoft\Windows NT\CurrentVersion\Svchost

Software\Microsoft\Windows NT\CurrentVersion\Svchost

Software\Microsoft\Windows NT\CurrentVersion\MgdSvchost

Software\Microsoft\Windows NT\CurrentVersion\MgdSvchost

\PIPE\

\PIPE\

Host Process for Windows Services

Host Process for Windows Services

6.1.7600.16385 (win7_rtm.090713-1255)

6.1.7600.16385 (win7_rtm.090713-1255)

svchost.exe

svchost.exe

Windows

Windows

Operating System

Operating System

6.1.7600.16385

6.1.7600.16385

svchost.exe_160_rwx_10000000_0004D000:

`.rsrc

`.rsrc

ServerKeyloggerU

ServerKeyloggerU