Sophos

Troj/DwnLdr-FHX

Category
Type
What to do
Prevalence low high

Summary

 
Affected operating systems Windows
Characteristics
  • Drops more malware
  • Installs itself in the registry
Included in our products from October 2006 (4.10)
Protection available since 5 September 2006 13:33:24 (GMT)
Detected by All Sophos products

Action

More Information

Troj/DwnLdr-FHX is a Trojan for the Windows platform.

When first run Troj/DwnLdr-FHX copies itself to <Windows>\lsass.exe and creates
the file <System>\rdriv.sys.

The file rdriv.sys is detected as Troj/Rootkit-W.

The file lsass.exe is registered as a new system driver service named "lsass",
with a display name of "Local Security Authority Subsystem Service" and a
startup type of automatic, so that it is started automatically during system
startup. The process <Windows>\lsass.exe is hidden. Registry entries are created
under:

HKLM\SYSTEM\CurrentControlSet\Services\lsass\

The file rdriv.sys is registered as a new system driver service named "rdriv",
with a display name of "rdriv". Registry entries are created under:

HKLM\SYSTEM\CurrentControlSet\Services\rdriv\

Troj/DwnLdr-FHX sets the following registry entries, disabling the automatic
startup of other software:

HKLM\SYSTEM\CurrentControlSet\Services\Messenger
Start
4

HKLM\SYSTEM\CurrentControlSet\Services\RemoteRegistry
Start
4

HKLM\SYSTEM\CurrentControlSet\Services\TlntSvr
Start
4

Registry entries are set as follows:

HKLM\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate
DoNotAllowXPSP2
1

HKLM\SOFTWARE\Microsoft\Ole
EnableDCOM
N

HKLM\SYSTEM\CurrentControlSet\Control\Lsa
restrictanonymous
1

Registry entries are created under:

HKLM\SOFTWARE\Microsoft\Security Center\
HKLM\SOFTWARE\Policies\Microsoft\WindowsFirewall\DomainProfile\
HKLM\SOFTWARE\Policies\Microsoft\WindowsFirewall\StandardProfile\

RSS|Atom
Get reports about the latest virus and spyware threats delivered to your computer