TROJ_KRYPTO.SMIU

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It also has rootkit capabilities, which enables it to hide its processes and files from the user.

It modifies the Internet Explorer Zone Settings.

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan drops the following component file(s):

• %System Root%\Recycle.Bin\{random name}

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It drops the following copies of itself into the affected system:

• %System Root%\Recycle.Bin\{random filename}.exe

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It creates the following folders:

• %System Root%\Recycle.Bin

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It terminates the execution of the copy it initially executed and executes the copy it drops instead.

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = "%System Root%\Recycle.Bin\{random filename}.exe /q"

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft Windows

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Recovery

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\PhishingFilter

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft Windows
{random value} = "{hex values}"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\PhishingFilter
EnabledV8 = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\PhishingFilter
ShownServiceDownBalloon = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Recovery
ClearBrowsingHistoryOnExit = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnOnPostRedirect = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnOnIntranet = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
GlobalUserOffline = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
ProxyHttp1.1 = "1"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnOnPost = "0"

(Note: The default value data of the said registry entry is 1.)

Rootkit Capabilities

This Trojan also has rootkit capabilities, which enables it to hide its processes and files from the user.

Web Browser Home Page and Search Page Modification

This Trojan modifies the Internet Explorer Zone Settings.