Trojan.Flush.K

Posted: June 20, 2012

Threat Metric

The Threat Meter is a malware assessment that SpywareRemove.com's research team is able to give every identifiable malware threat. Our Threat Meter includes several criteria based off of specific malware threats to value their severity, reach and volume. The Threat Meter is able to give you a numerical breakdown of each threat's initial Threat Level, Detection Count, Volume Count, Trend Path and Percentage Impact. The overall ranking of each threat in the Threat Meter is a basic breakdown of how all threats are ranked within our own extensive malware database. The scoring for each specific malware threat can be easily compared to other emerging threats to draw a contrast in its particular severity. The Threat Meter is a useful tool in the endeavor of seeking a solution to remove a threat or pursue additional analytical research for all types of computer users.

The following fields listed on the Threat Meter containing a specific value, are explained in detail below:

Threat Level: The threat level scale goes from 1 to 10 where 10 is the highest level of severity and 1 is the lowest level of severity. Each specific level is relative to the threat's consistent assessed behaviors collected from SpyHunter's risk assessment model.

Detection Count: The collective number of confirmed and suspected cases of a particular malware threat. The detection count is calculated from infected PCs retrieved from diagnostic and scan log reports generated by SpyHunter.

Volume Count: Similar to the detection count, the Volume Count is specifically based on the number of confirmed and suspected threats infecting systems on a daily basis. High volume counts usually represent a popular threat but may or may not have infected a large number of systems. High detection count threats could lay dormant and have a low volume count. Criteria for Volume Count is relative to a daily detection count.

Trend Path: The Trend Path, utilizing an up arrow, down arrow or equal symbol, represents the level of recent movement of a particular threat. Up arrows represent an increase, down arrows represent a decline and the equal symbol represent no change to a threat's recent movement.

% Impact (Last 7 Days): This demonstrates a 7-day period change in the frequency of a malware threat infecting PCs. The percentage impact correlates directly to the current Trend Path to determine a rise or decline in the percentage.

Threat Level:	9/10
Infected PCs:	74

First Seen:	June 22, 2012
OS(es) Affected:	Windows

Trojan.Flush.K is a particularly infamous browser hijacker that changes your computer's DNS settings to redirect your browser to unwanted and potentially harmful sites. Although, at the time of this writing, all confirmed Trojan.Flush.K servers have been shut down, recent action by the ISC has also taken down their clean 'substitute' servers. This can result in Trojan.Flush.K-infected PCs suffering from a total loss of Internet connectivity until Trojan.Flush.K is removed. Even though this side effect is rather alarming, SpywareRemove.com malware researchers recommend that you keep calm and delete Trojan.Flush.K in the same way that you'd deal with any type of browser hijacker: by scanning your computer with an appropriate brand of anti-malware application. Doing this and restoring your original DNS settings will re-enable Internet access as normal.

Trojan.Flush.K – the Browser-Redirecting Trojan That's Turned into an Inadvertent Internet Blockade

Trojan.Flush.K has been identified since 2007 by various names, including Trojan.dnschanger and similar PC threats like Trojan:BAT/Dnschanger.B, Trojan:Win32/Dnschanger.AI and several variants of Alueron. The trademark features of Trojan.Flush.K and its relatives are attacks against the infected PC's Domain Name System or DNS settings. Since these settings control your computer's ability to translate website addresses into actual destinations, these attacks have allowed Trojan.Flush.K to redirect its victims to any other type of website at its pleasure, including sites that host malicious content (such as phishing attacks and drive-by-download scripts).

SpywareRemove.com malware researchers note that similar attacks can still be functional for other Trojans, but also that all servers associated with Trojan.Flush.K have been shut down under a court order. While Trojan.Flush.K may not be able to cause browser redirects or otherwise harm your computer anymore, its DNS changes may still hinder your PC's ability to access the Internet. Loss of Internet connectivity due to these circumstances can only be remedied by removing Trojan.Flush.K and undoing its DNS changes, which should be achievable with any good anti-malware application.

Flushing Trojan.Flush.K Down the Digital Toilet

If you've experienced a loss of Internet access since July 9th, your PC may be one of the hundreds of thousands that are still estimated to be infected with Trojan.Flush.K. Fortunately, detecting, containing and detecting Trojan.Flush.K infections are all considered relatively easy tasks with appropriate anti-malware products in-hand, and, by itself, SpywareRemove.com malware researchers rate Trojan.Flush.K as a low-level PC threat.

Like many browser hijackers, Trojan.Flush.K was designed to attack only Windows-based PCs, including the XP, 98, 95, 2K, Me and NT platforms. However, the basic DNS-changing attacks that Trojan.Flush.K uses can be exploited by many other types of browser hijackers, and SpywareRemove.com malware researchers also warn that contact with sites that Trojan.Flush.K promotes may result in infection by greater PC threats than Trojan.Flush.K. Due to its modifications to the Registry and other Windows components, removal of Trojan.Flush.K by manual methods is not recommended.

Technical Details

File System Modifications

Tutorials: If you wish to learn how to remove malware components manually, you can read the tutorials on how to find malware, kill unwanted processes, remove malicious DLLs and delete other harmful files. Always be sure to back up your PC before making any changes.

The following files were created in the system:

file.exe

File name: file.exe
Size: 198.55 KB (198557 bytes)
MD5: b72668b4a3853b0c3675b91511481b95
Detection count: 93
File type: Executable File
Mime Type: unknown/exe
Group: Malware file
Last Updated: June 28, 2012

%UserProfile%\Local Settings\Temp\step1.exe

File name: %UserProfile%\Local Settings\Temp\step1.exe
File type: Executable File
Mime Type: unknown/exe
Group: Malware file

%UserProfile%\Local Settings\Temp\svchost.exe

File name: %UserProfile%\Local Settings\Temp\svchost.exe
File type: Executable File
Mime Type: unknown/exe
Group: Malware file

%UserProfile%\Local Settings\Temp\step2.exe

File name: %UserProfile%\Local Settings\Temp\step2.exe
File type: Executable File
Mime Type: unknown/exe
Group: Malware file

%ProgramFiles%\DirectVideo\Uninstall.exe

File name: %ProgramFiles%\DirectVideo\Uninstall.exe
File type: Executable File
Mime Type: unknown/exe
Group: Malware file

%UserProfile%\Start Menu\Programs\DirectVideo\Uninstall.lnk

File name: %UserProfile%\Start Menu\Programs\DirectVideo\Uninstall.lnk
File type: Shortcut
Mime Type: unknown/lnk
Group: Malware file

%System%\kd[3 RANDOM CHARACTERS].exe

File name: %System%\kd[3 RANDOM CHARACTERS].exe
File type: Executable File
Mime Type: unknown/exe
Group: Malware file

More files

Registry Modifications

The following newly produced Registry Values are:

HKEY..\..\{CLSID Path}HKEY_CLASSES_ROOT\DirectVideo\CLSID\"Default" = "{6BF52A52-394A-11D3-B153-00C04F79FAA6}"HKEY..\..\{Value}HKEY_LOCAL_MACHINE%\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\"System" = "kd???.exe"HKEY_ALL_USERS\Software\DirectVideo\"Default" = "%ProgramFiles%\DirectVideo"HKEY_ALL_USERS\Software\DirectVideo\"Start Menu Folder" = "DirectVideo"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\DirectVideo\"DisplayIcon" = "%ProgramFiles%\DirectVideo\Uninstall,0"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\DirectVideo\"DisplayName" = "DirectVideo"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\DirectVideo\"NoRepair" = "0x00000001"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\DirectVideo\"UninstallString" = "%ProgramFiles%\DirectVideo\Uninstall.exe"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\DirectVideo\"InstallLocation" = "%ProgramFiles%\DirectVideo"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\DirectVideo\"NoModify" = "0x00000001"HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\[RANDOM CLSID]\"DhcpNameServer" = "85.255.115.21,85.255.112.91"HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\[RANDOM CLSID]\"NameServer" = "85.255.115.21,85.255.112.91"HKEY..\..\..\..{Subkeys}HKEY_LOCAL_MACHINE%\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\DirectVideoHKEY_CLASSES_ROOT%\DirectVideoHKEY_ALL_USERS%\Software\DirectVideoHKEY_CLASSES_ROOT%\DirectVideo\CLSID