arrow_back
search
close

BKDR_JOANAP.AC

November 21, 2012
 Analysis by: Marfel Tiamzon
 Modified by: Jaime Benigno Reyes
 ALIASES:

Backdoor:Win32/Joanap.A (Microsoft); Worm.Win32.Agent.age (Kaspersky)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003, Windows 7

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


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

  TECHNICAL DETAILS

File Size:

208,896 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

28 Sep 2011

Arrival Details

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

Autostart Technique

This backdoor registers its dropped component as a system service to ensure its automatic execution at every system startup. It does this by creating the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv
Type = "20"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv
Start = "2"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv
ErrorControl = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv
ImagePath = "%System Root%\system32\svchost.exe -k SCardPrv"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv
DisplayName = "SmartCard Protector"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv
ObjectName = "LocalSystem"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv
Description = "Manages and controls access to a smart card inserted into a smart card reader attached to the computer and protect from others. "

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv\Parameters
ServiceDll = "%SystemRoot%\system32\scardprv.dll"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc
Type = "20"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc
Start = "2"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc
ErrorControl = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc
ImagePath = "%SystemRoot%\system32\svchost.exe -k Wmmvsvc"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc
DisplayName = "Windows Media Management Driver Extensions"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc
ObjectName = "LocalSystem"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc
Description = "Provides Windows Media management information to and from drivers. "

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc\Parameters
ServiceDll = "%SystemRoot%\system32\Wmmvsvc.dll"

It registers its dropped component as a system service to ensure its automatic execution at every system startup. It does this by creating the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SCardPrv

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Wmmvsvc

Other System Modifications

This backdoor adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\SvcHost
SCardPrv = "SCardPrv"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\SvcHost
Wmmvsvc = "Wmmvsvc"

Dropping Routine

This backdoor drops the following files:

  • %System%\KB25879.dat
  • %System%\mssscardprv.ax
  • %System%\scardprv.dll - also detected as BKDR_JOANAP.AC
  • %System%\Wmmvsvc.dll - also detected as BKDR_JOANAP.AC

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

8.472.05

FIRST VSAPI PATTERN DATE:

04 Oct 2011

VSAPI OPR PATTERN File:

8.473.00

VSAPI OPR PATTERN Date:

05 Oct 2011

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

Restart in Safe Mode

[ Learn More ]

Step 3

Delete this registry value

[ 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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SvcHost
    • SCardPrv = "SCardPrv"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SvcHost
    • Wmmvsvc = "Wmmvsvc"

Step 4

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_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • SCardPrv
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • Wmmvsvc

Step 5

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.
  • %System%\KB25879.dat
  • %System%\mssscardprv.ax
  • %System%\scardprv.dll
  • %System%\Wmmvsvc.dll

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_JOANAP.AC. 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.


Did this description help? Tell us how we did.