TROJ_FAKEAV.KPP

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 employs registry shell spawning by adding certain registry entries. This allows this malware to execute even when other applications are opened.

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 copies of itself into the affected system and executes them:

• C:\Documents and Settings\All Users\Application Data\{random hex string}\{random hex string}.exe

Autostart Technique

This Trojan employs registry shell spawning to ensure its execution when certain file types are accessed by adding the following entries:

HKEY_CLASSES_ROOT\.exe
(Default) = "{first 5 characters of malware filename}"

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

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}
(Default) = "Application"

HKEY_CLASSES_ROOT\%s
(Default) = "{first 5 characters of malware filename}"

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}
Content Type = "application/x-msdownload"

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
open\command
IsolatedCommand = "%1" %*

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
runas\command
(Default) = "C:\Documents and Settings\All Users\Application Data\{random hex string}\{random hex string}.exe" -s "%1" %*

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
open\command
(Default) = "C:\Documents and Settings\All Users\Application Data\{random hex string}\{random hex string}.exe" -s "%1" %*

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
start\command
(Default) = "%1" %*

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
runas\command
IsolatedCommand = "%1" %*

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
start\command
IsolatedCommand = "%1" %*

Other System Modifications

This Trojan adds the following registry entries as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center\svc
FirewallOverride = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center\svc
FirewallDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center\svc
UpdatesDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center\svc
AntiVirusDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center\svc
AntiVirusOverride = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
FirewallOverride = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
FirewallDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
UpdatesDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
AntiVirusDisableNotify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center
AntiVirusOverride = "1"

HKEY_CLASSES_ROOT\%s

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\DefaultIcon

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\DefaultIcon
(Default) = "%1"

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
open

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
open\command

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
runas

HKEY_CLASSES_ROOT\{random value}\shell\
runas\command

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
start

HKEY_CLASSES_ROOT\{first 5 characters of malware filename}\shell\
start\command

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Security Center\svc