Backdoor.Win32.Kelihos_25789eec9e

Dynamic Analysis

Payload

No specific payload has been found.

Process activity

The Backdoor creates the following process(es):

temp3830475590.exe:548
%original file name%.exe:1336

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

temp1033573107.exe:624

File activity

The process %original file name%.exe:1336 makes changes in the file system.

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

%Documents and Settings%\%current user%\Local Settings\Temp\temp1033573107.exe (3910 bytes)
%Documents and Settings%\%current user%\Local Settings\Temp\temp3830475590.exe (6377 bytes)

The process temp1033573107.exe:624 makes changes in the file system.

The Backdoor deletes the following file(s):

%Documents and Settings%\%current user%\Local Settings\Temp\tmp.exe (0 bytes)

Registry activity

The process temp3830475590.exe:548 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "4E E4 C7 D1 0B A1 C1 C9 C6 52 6F 1B 7D AC 6D E0"

The process %original file name%.exe:1336 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "C4 96 7D 03 3D 3F F9 A3 B4 DA 91 1B D8 B5 12 A3"

The process temp1033573107.exe:624 makes changes in the system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "CE 10 F7 D3 88 2E 84 DD DF FB FC 61 33 99 17 69"

[HKCU\Software\Microsoft\Notepad]
"sizeCompletedValid" = "DHuAxdAeTvCuxv/f3z/LP8OgiKX7ifHeA 1h 1jyTcdKOnQl4vfyWwPXssa9Y0gQoQ=="

[HKCU\Software\Sysinternals\Process Monitor]
"UrlEnabledUse" = "80"

[HKLM\System\CurrentControlSet\Services\nm\Parameters]
"EnableStationQueries" = "1"
"ComputerName" = "XP3"

[HKCU\Software\Microsoft\Notepad]
"infoPlayedCurrent" = "00 00 00 00 00 00 00 00"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common AppData" = "%Documents and Settings%\All Users\Application Data"

[HKCU\Software\Microsoft\Internet Explorer\Main]
"DBSavedUse" = "A2 49 4D F3 D9 1E 9F 88 01 01 08 6A 00 03 39 04"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

[HKCU\Software\Sysinternals\Process Monitor]
"FlagsModifiedValid" = "00 00 00 00 00 00 00 00"

[HKCU\Software\Microsoft\Notepad]
"styleModifiedPrev" = "80"

[HKCU\Software\Microsoft\Internet Explorer\Main]
"PlatformCompressedValid" = "00 00 00 00 00 00 00 00"
"PersistentLocalizedName" = "24 80 F9 7F 7A 08 E8 3B 9B 03 91 C6 19 4F 99 47"

[HKCU\Software\Sysinternals\Process Monitor]
"DefaultCompressedRecord" = "24 80 F9 7F 73 BC 04 50 31 0A 92 96 47 40 9F AA"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Local AppData" = "%Documents and Settings%\%current user%\Local Settings\Application Data"

[HKCU\Software\Microsoft\Notepad]
"activeModifiedTheme" = "24 80 F9 7F 87 51 D1 F5 0A 70 98 FD F0 F7 45 48"

[HKCU\Software\Microsoft\Internet Explorer\Main]
"RecordEnabledCheck" = "80"

[HKCU\Software\Sysinternals\Process Monitor]
"RecordModifiedMax" = "DHuAxdAeTvCuxv/f3z/LP8OgiKX7ifHeA 1h 1jyTcdKOnQl4vfyWwPXssa9Y0gQoQ=="

[HKLM\System\CurrentControlSet\Services\nm\Parameters]
"UserName" = "%CurrentUserName%"

[HKCU\Software\Microsoft\Internet Explorer\Main]
"LineLoadedQuick" = "DHuAxdAeTvCuxv/f3z/LP8OgiKX7ifHeA 1h 1jyTcdKOnQl4vfyWwPXssa9Y0gQoQ=="

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

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
"NetworkChecker" = "C:\DOCUME~1\"%CurrentUserName%"\LOCALS~1\Temp\temp1033573107.exe"

Network activity (URLs)

URL	IP
hxxp://159.224.26.217/mod1/b0ber01.exe (Malicious)
hxxp://37.75.103.48/mod2/b0ber01.exe (Malicious)

HOSTS file anomalies

No changes have been detected.

Rootkit activity

No anomalies have been detected.

Propagation

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):

   temp3830475590.exe:548
   %original file name%.exe:1336
   

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

   %Documents and Settings%\%current user%\Local Settings\Temp\temp1033573107.exe (3910 bytes)
   %Documents and Settings%\%current user%\Local Settings\Temp\temp3830475590.exe (6377 bytes)

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

   [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   "NetworkChecker" = "C:\DOCUME~1\"%CurrentUserName%"\LOCALS~1\Temp\temp1033573107.exe"

5. Clean the Temporary Internet Files folder, which may contain infected files (How to clean Temporary Internet Files folder).
   
6. Reboot the computer.
   

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

Static Analysis

Network Activity

Map

Strings from Dumps