Analysis by: Christopher Daniel So

ALIASES:

Trojan:Win32/Evadiped.A (Microsoft), BackDoor-EDY.b (McAfee), Win32/BHO.NMM trojan (Nod32), Trj/Exebot.A (Panda), Trojan.ExeDot.dhg (QuickHeal), TR/ExeDot.dhf (AntiVir), Trojan.Win32.ExeDot (Ikarus), W32/BHO.HET!tr (Fortinet)

 PLATFORM:

Windows 2000, XP, Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

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 may be dropped by other malware.

It does not have any backdoor routine.

It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system. As of this writing, the said sites are inaccessible.

It does not have any information-stealing capability.

  TECHNICAL DETAILS

File Size: Varies
File Type: DLL
Memory Resident: Yes
Initial Samples Received Date: 07 Oct 2010

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.

It may be dropped by the following malware:

  • TROJ_DROPPER.OMJ

Autostart Technique

This Trojan registers itself as a BHO to ensure its automatic execution every time Internet Explorer is used by adding the following registry keys:

HKEY_CLASSES_ROOT\Interface\{986A8AC1-AB4D-4F41-9068-4B01C0197867}

HKEY_CLASSES_ROOT\TypeLib\{8E3C68CD-F500-4A2A-8CB9-132BB38C3573}

HKEY_CLASSES_ROOT\CLSID\{AFD4AD01-58C1-47DB-A404-FBE00A6C5486}

HKEY_CLASSES_ROOT\AppID\{A0E1054B-01EE-4D57-A059-4D99F339709F}

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects\{AFD4AD01-58C1-47DB-A404-FBE00A6C5486}

HKEY_CLASSES_ROOT\AppID\main.DLL

HKEY_CLASSES_ROOT\main.BHO

HKEY_CLASSES_ROOT\main.BHO.1

It registers itself as a BHO to ensure its automatic execution every time Internet Explorer is used by adding the following registry entries:

HKEY_CLASSES_ROOT\CLSID\{AFD4AD01-58C1-47DB-A404-FBE00A6C5486}\
InProcServer32
(Default) = "{malware path and file name}.dll"

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CLASSES_ROOT\‚”#˜‚

Backdoor Routine

This Trojan does not have any backdoor routine.

Download Routine

This Trojan connects to the following URL(s) to download its component file(s):

  • u.{BLOCKED}compile.com
  • k.{BLOCKED}xad.com

It saves the files it downloads using the following names:

  • %User Temp%\{random file name}.TMP
  • %Current Folder%\{malware name}.sig

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.)

It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

As of this writing, the said sites are inaccessible.

Information Theft

This Trojan does not have any information-stealing capability.

Other Details

This Trojan does the following:

  • Checks and reports to the URLs above if the following processes are running in the system:
    • ACAAS.exe
    • ACAEGMr.exe
    • ACAIS.exe
    • ACALS.exe
    • ACASP.exe
    • AFMain.exe
    • AGIDSUI.exe
    • ALMon.exe
    • ALsvc.exe
    • APVXDWIN.EXE
    • AVGIDSAgent.exe
    • AVGIDSMonitor.exe
    • AVGIDSWatcher.exe
    • AhnSD.exe
    • AhnSDsv.exe
    • AluSchedulerSvc.exe
    • ApVxdWin.exe
    • CAGlobal.exe
    • CAGlobalLight.exe
    • CAPPActiveProtection.exe
    • CCSVCHST.EXE
    • CClaw.exe
    • CounterSpy.exe
    • EMLPROUI.EXE
    • EMLPROXY.EXE
    • FAMEH32.exe
    • FCH32.EXE
    • FPAVServer.exe
    • FProtTray.exe
    • FSM32.EXE
    • FSMA32.EXE
    • FSMB32.exe
    • HFACSvc.exe
    • HrRes.exe
    • IFace.exe
    • ISWSVC.exe
    • ITMRTSVC.exe
    • K7EmlPxy.exe
    • K7FWSrvc.exe
    • K7PSSrvc.exe
    • K7RTScan.exe
    • K7SysMon.exe
    • K7SysTry.exe
    • K7TSMngr.exe
    • K7TSecurity.exe
    • MSASCui.exe
    • MSProxy.ahn
    • McNASvc.exe
    • McProxy.exe
    • McSACore.exe
    • Mcshield.exe
    • MpfSrv.exe
    • MsMpEng.exe
    • Nbrowser.exe
    • Nip.exe
    • Njeeves.exe
    • Nsesvc.exe
    • Nvcoas.exe
    • ONLINENT.EXE
    • ONLNSVC.EXE
    • OPSSVC.EXE
    • OcHealthMon.exe
    • PAVSRV51.EXE
    • PPCtlPriv.exe
    • PSANHost.exe
    • PSHost.exe
    • PSUNMain.exe
    • PXAgent.exe
    • PXConsole.exe
    • PavBckPT.exe
    • PavFnSvr.exe
    • PavPrSrv.exe
    • PslmSvc.exe
    • QOELoader.exe
    • QUHLPSVC.EXE
    • RavMon.exe
    • RavTask.exe
    • RsTray.exe
    • SAVAdminService.exe
    • SBCSSvc.exe
    • SBCSTray.exe
    • SCANMSG.EXE
    • SCANWSCS.EXE
    • SavService.exe
    • SfCtlCom.exe
    • SpIDerAgent.exe
    • SpIDerMI.exe
    • TMBMSRV.exe
    • TRAYSSER.EXE
    • TSCFCommander.exe
    • TSCFPlatformCOMSvr.exe
    • TmPfw.exe
    • TmProxy.exe
    • UPSCHD.EXE
    • UfNai.exe
    • UfSeAgnt.exe
    • UfUpdUi.exe
    • UmxAgent.exe
    • UmxCfg.exe
    • UmxFwHlp.exe
    • UmxPol.exe
    • WEBPROXY.EXE
    • WinSSUI.exe
    • Zanda.exe
    • Zlh.exe
    • acs.exe
    • ashDisp.exe
    • ashMaiSv.exe
    • ashServ.exe
    • ashWebSv.exe
    • aswUpdSv.exe
    • avesvc.exe
    • avgam.exe
    • avgamsvr.exe
    • avgas.exe
    • avgcc.exe
    • avgcsrvx.exe
    • avgemc.exe
    • avgfws8.exe
    • avgnsx.exe
    • avgrsx.exe
    • avgtray.exe
    • avgupd.exe
    • avgupsvc.exe
    • avgwdsvc.exe
    • avgwsvc.exe
    • avp.exe
    • avpmapp.exe
    • avwebgrd.exe
    • caavguiscan.exe
    • capfasem.exe
    • cappactiveprotection.exe
    • casc.exe
    • casecuritycenter.exe
    • cavrid.exe
    • ccSvcHst.exe
    • ccschedulersvc.exe
    • cctray.exe
    • drwebscd.exe
    • egui.exe
    • ekrn.exe
    • elogsvc.exe
    • forsp.exe
    • fsaua.exe
    • fsav32.exe
    • fsavgui.exe
    • fsdfwd.exe
    • fsgk32.exe
    • fsgk32st.exe
    • fsguidll.exe
    • fspc.exe
    • fsqh.exe
    • fssm32.exe
    • fsus.exe
    • guard.exe
    • guardxkickoff.exe
    • guardxservice.exe
    • guardxup.exe
    • hcontain.exe
    • hpcsvc.exe
    • hsvcmod.exe
    • isafe.exe
    • livesrv.exe
    • mcagent.exe
    • mcmscsvc.exe
    • mcshell.exe
    • mcsysmon.exe
    • mcupdmgr.exe
    • mcvsmap.exe
    • mcvsshld.exe
    • mdmcls32.exe
    • msfwsvc.exe
    • msksrver.exe
    • npcsvc32.exe
    • npfsvc32.exe
    • npfuser.exe
    • nprosec.exe
    • nuaa.exe
    • nvcsched.exe
    • nvoy.exe
    • op_mon.exe
    • prevx.exe
    • psksvc.exe
    • qhfw.exe
    • rsnetsvr.exe
    • seccenter.exe
    • spiderml.exe
    • spidernt.exe
    • spidersgate.exe
    • spiderui.exe
    • svcprs32.exe
    • symlcsvc.exe
    • vba32ldr.exe
    • vbcmserv.exe
    • vbsystry.exe
    • vetmsg.exe
    • virCatch.exe
    • virusutilities.exe
    • vrfwsock.exe
    • vrfwsvc.exe
    • vrmonnt.exe
    • vrmonsvc.exe
    • vrrepair.exe
    • vrscan.exe
    • vsmon.exe
    • vsserv.exe
    • winss.exe
    • winssnotify.exe
    • xcommsvr.exe
    • zlclient.exe
  • It does not have rootkit capabilities.

  SOLUTION

Minimum Scan Engine: 8.900
VSAPI PATTERN File: 7.796.11
VSAPI PATTERN Date: 27 Jan 2011
VSAPI PATTERN Date: 1/27/2011 12:00:00 AM
FIRST VSAPI PATTERN FILE: 7.552.12
FIRST VSAPI PATTERN DATE: 19 Oct 2010

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Close all opened browser windows

Step 3

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CLASSES_ROOT
    • main.BHO
  • In HKEY_CLASSES_ROOT
    • main.BHO.1
  • In HKEY_CLASSES_ROOT
    • ‚”#˜‚
  • In HKEY_CLASSES_ROOT\AppID
    • main.DLL
  • In HKEY_CLASSES_ROOT\AppID
    • {A0E1054B-01EE-4D57-A059-4D99F339709F}
  • In HKEY_CLASSES_ROOT\CLSID
    • {AFD4AD01-58C1-47DB-A404-FBE00A6C5486}
  • In HKEY_CLASSES_ROOT\Interface
    • {986A8AC1-AB4D-4F41-9068-4B01C0197867}
  • In HKEY_CLASSES_ROOT\TypeLib
    • {8E3C68CD-F500-4A2A-8CB9-132BB38C3573}
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects
    • {AFD4AD01-58C1-47DB-A404-FBE00A6C5486}

Step 4

Search and delete these files

[ Learn More ]
There may be some component files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden files and folders in the search result. %User Temp%\{random file name}.TMP
%Current Folder%\{malware name}

Step 5

Scan your computer with your Trend Micro product to delete files detected as TROJ_EXEDOT.SMA. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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