Backdoor.Win32.Kelihos_d390b8c9f3

Dynamic Analysis

Payload

No specific payload has been found.

Process activity

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

d390b8c9f3d1fced6a9796e9fff4a6a2.exe:136

File activity

The process d390b8c9f3d1fced6a9796e9fff4a6a2.exe:136 makes changes in a file system.

The Backdoor deletes the following file(s):

C:\tmp.exe (0 bytes)

Registry activity

The process d390b8c9f3d1fced6a9796e9fff4a6a2.exe:136 makes changes in a system registry.

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

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "F5 89 50 73 7A EC 99 27 B9 FD 0D A2 22 AE E8 E9"

[HKCU\Software\Microsoft\Notepad]
"sizeCompletedValid" = "DDx3PlZDm31KczYam0kakzqtbhawi120CxPwaxDEgLlnFXhnO4nRdRINO1oAwdPIMA=="

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

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

[HKLM\System\CurrentControlSet\Services\nm\Parameters]
"ComputerName" = "XP7"

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

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

[HKCU\Software\Microsoft\Internet Explorer\Main]
"DBSavedUse" = "A2 49 4D F3 D9 1E 9F 88 01 01 08 61 00 02 01 10"

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

[HKCU\Software\Microsoft\Internet Explorer\Main]
"PlatformCompressedValid" = "00 00 00 00 00 00 00 00"

[HKCU\Software\Microsoft\Internet Explorer\Main]
"PersistentLocalizedName" = "06 80 F9 7F 7A 50 66 11 B4 92 25 E4 4C 29 03 5A"

[HKCU\Software\Sysinternals\Process Monitor]
"DefaultCompressedRecord" = "06 80 F9 7F 73 44 07 2D 44 7E 1C 65 B6 91 78 25"

[HKCU\Software\Microsoft\Notepad]
"activeModifiedTheme" = "06 80 F9 7F 87 21 F3 6A 61 DE 67 1A 03 7E 76 2F"

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

[HKCU\Software\Sysinternals\Process Monitor]
"RecordModifiedMax" = "DDx3PlZDm31KczYam0kakzqtbhawi120CxPwaxDEgLlnFXhnO4nRdRINO1oAwdPIMA=="

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

[HKCU\Software\Microsoft\Internet Explorer\Main]
"LineLoadedQuick" = "DDx3PlZDm31KczYam0kakzqtbhawi120CxPwaxDEgLlnFXhnO4nRdRINO1oAwdPIMA=="

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]
"NetworkVerifyer" = "c:\d390b8c9f3d1fced6a9796e9fff4a6a2.exe"

Network activity (URLs)

URL	IP
hxxp://46.172.134.81/index.htm (Malicious)
hxxp://46.172.134.81/start.htm (Malicious)

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 the original Backdoor's process (How to End a Process With the Task Manager).
2. Delete the original Backdoor file.
   
3. Delete the following value(s) in the autorun key (How to Work with System Registry):

   [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   "NetworkVerifyer" = "c:\d390b8c9f3d1fced6a9796e9fff4a6a2.exe"

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