PUA.Win32.Koal.AZ
Riskware/Koal (FORTINET); a variant of Win32/Koal.A (NOD32)
Windows
Threat Type: Potentially Unwanted Application
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
This Potentially Unwanted Application arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It does not have any propagation routine.
It does not have any backdoor routine.
It does not have any information-stealing capability.
TECHNICAL DETAILS
Arrival Details
This Potentially Unwanted Application 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 Potentially Unwanted Application drops the following files:
- %Application Data%\configtools.log → contains logs of process done
- %Application Data%\configtools.dat → contains base64-encoded %System%\KoalCspWrapper.ocx file, and added trusted sites and certificates
- %System%\KoalCspWrapper.ocx
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
Autostart Technique
This Potentially Unwanted Application adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-4}\InprocServer32
(Default) = %System%\KOALCS~1.OCX
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\InprocServer32
(Default) = %System%\KOALCS~1.OCX
Other System Modifications
This Potentially Unwanted Application adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}\1.0
(Default) = KoalCspWrapper ActiveX Control module
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}\1.0\
FLAGS
(Default) = 2
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}\1.0\
0\win32
(Default) = %System%\KoalCspWrapper.ocx
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}
(Default) = _DKoalCspWrapper
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}\ProxyStubClsid
(Default) = {Proxy Stub ID}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}\ProxyStubClsid32
(Default) = {Proxy Stub ID}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}\TypeLib
(Default) = {Generated ID-1}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}\TypeLib
Version = 1.0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-3}
(Default) = _DKoalCspWrapperEvents
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-3}\ProxyStubClsid
(Default) = {Proxy Stub ID}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-3}\ProxyStubClsid32
(Default) = {Proxy Stub ID}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-3}\TypeLib
(Default) = {Generated ID-1}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-3}\TypeLib
Version = 1.0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-4}
(Default) = KoalCspWrapper Property Page
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-4}\InprocServer32
(Default) = %System%\KOALCS~1.OCX
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
KoalEAClient.CspWrapper.1
(Default) = KoalCspWrapper Control
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
KoalEAClient.CspWrapper.1\CLSID
(Default) = {Generated ID-5}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}
(Default) = KoalCspWrapper Control
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\ProgID
(Default) = KoalEAClient.CspWrapper.1
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\ToolboxBitmap32
(Default) = %System%\KOALCS~1.OCX, 1
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\MiscStatus
(Default) = 0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\MiscStatus\
1
(Default) = 131473
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\TypeLib
(Default) = {Generated ID-1}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\Version
(Default) = 1.0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\InprocServer32
ThreadingModel = Apartment
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Component Categories\{ID}
409 = Controls safely initializable from persistent data!
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Component Categories\{ID}
409 = Controls safely scriptable!
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
SystemCertificates\ROOT\Certificates\
b26fa75369d6fd879204d8e67fcc105ef35fcd84
Blob = {Blob data}
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
SystemCertificates\CA\Certificates\
d2ea461e09eeb661f39dd88f63b2d1b592a7d341
Blob = {Blob data}
Propagation
This Potentially Unwanted Application does not have any propagation routine.
Backdoor Routine
This Potentially Unwanted Application does not have any backdoor routine.
Rootkit Capabilities
This Potentially Unwanted Application does not have rootkit capabilities.
Information Theft
This Potentially Unwanted Application does not have any information-stealing capability.
Other Details
This Potentially Unwanted Application adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}\1.0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}\1.0\
FLAGS
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}\1.0\
0
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}\1.0\
0\win32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
TypeLib\{Generated ID-1}\1.0\
HELPDIR
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}\ProxyStubClsid
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}\ProxyStubClsid32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{Generated ID-2}\TypeLib
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-4}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-4}\InprocServer32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
KoalEAClient.CspWrapper.1
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
KoalEAClient.CspWrapper.1\CLSID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\ProgID
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\InprocServer32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\ToolboxBitmap32
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\MiscStatus
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\MiscStatus\
1
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\Control
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\TypeLib
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\Version
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\Implemented Categories
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-5}\Implemented Categories\
{ID}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-6}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-6}\Implemented Categories
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{Generated ID-6}\Implemented Categories\
{ID}
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
SystemCertificates\ROOT\Certificates\
b26fa75369d6fd879204d8e67fcc105ef35fcd84
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
SystemCertificates\CA\Certificates\
d2ea461e09eeb661f39dd88f63b2d1b592a7d341
It displays the following images:
It does the following:
- It adds the following sites to the system's trusted sites:
- http://{BLOCKED}.{BLOCKED}.156.9
- http://{Any subdomain}.{BLOCKED}.gov.cn
- https://ytb.{BLOCKED}.gov.cn
- It installs the following certificates in the system:
- [Trusted Root Certification Authorities]
Issued by: NBSROOT
Issued to: NBSROOT
Thumbprint: b26fa75369d6fd879204d8e67fcc105ef35fcd84 - [Intermediate Certification Authorities]
Issued by: NBSROOT
Issued to: AHCA
Thumbprint: d2ea461e09eeb661f39dd88f63b2d1b592a7d341
- [Trusted Root Certification Authorities]
It does not exploit any vulnerability.
SOLUTION
Step 1
Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.
Step 2
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 3
Restart in Safe Mode
Step 4
Delete this registry value
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\Classes\TypeLib\{Generated ID-1}\1.0
- (Default) = KoalCspWrapper ActiveX Control module
- (Default) = KoalCspWrapper ActiveX Control module
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{Generated ID-1}\1.0\FLAGS
- (Default) = 2
- (Default) = 2
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib\{Generated ID-1}\1.0\0\win32
- (Default) = %System%\KoalCspWrapper.ocx
- (Default) = %System%\KoalCspWrapper.ocx
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-2}
- (Default) = _DKoalCspWrapper
- (Default) = _DKoalCspWrapper
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-2}\ProxyStubClsid
- (Default) = {Proxy Stub ID}
- (Default) = {Proxy Stub ID}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-2}\ProxyStubClsid32
- (Default) = {Proxy Stub ID}
- (Default) = {Proxy Stub ID}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-2}\TypeLib
- (Default) = {Generated ID-1}
- (Default) = {Generated ID-1}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-2}\TypeLib
- Version = 1.0
- Version = 1.0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-3}
- (Default) = _DKoalCspWrapperEvents
- (Default) = _DKoalCspWrapperEvents
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-3}\ProxyStubClsid
- (Default) = {Proxy Stub ID}
- (Default) = {Proxy Stub ID}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-3}\ProxyStubClsid32
- (Default) = {Proxy Stub ID}
- (Default) = {Proxy Stub ID}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-3}\TypeLib
- (Default) = {Generated ID-1}
- (Default) = {Generated ID-1}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{Generated ID-3}\TypeLib
- Version = 1.0
- Version = 1.0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-4}
- (Default) = KoalCspWrapper Property Page
- (Default) = KoalCspWrapper Property Page
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-4}\InprocServer32
- (Default) = %System%\KOALCS~1.OCX
- (Default) = %System%\KOALCS~1.OCX
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\KoalEAClient.CspWrapper.1
- (Default) = KoalCspWrapper Control
- (Default) = KoalCspWrapper Control
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\KoalEAClient.CspWrapper.1\CLSID
- (Default) = {Generated ID-5}
- (Default) = {Generated ID-5}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}
- (Default) = KoalCspWrapper Control
- (Default) = KoalCspWrapper Control
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}\ProgID
- (Default) = KoalEAClient.CspWrapper.1
- (Default) = KoalEAClient.CspWrapper.1
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}\ToolboxBitmap32
- (Default) = %System%\KOALCS~1.OCX, 1
- (Default) = %System%\KOALCS~1.OCX, 1
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}\MiscStatus
- (Default) = 0
- (Default) = 0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}\MiscStatus\1
- (Default) = 131473
- (Default) = 131473
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}\TypeLib
- (Default) = {Generated ID-1}
- (Default) = {Generated ID-1}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}\Version
- (Default) = 1.0
- (Default) = 1.0
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}\InprocServer32
- ThreadingModel = Apartment
- ThreadingModel = Apartment
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Component Categories\{ID}
- 409 = Controls safely initializable from persistent data!
- 409 = Controls safely initializable from persistent data!
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Component Categories\{ID}
- 409 = Controls safely scriptable!
- 409 = Controls safely scriptable!
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\ROOT\Certificates\b26fa75369d6fd879204d8e67fcc105ef35fcd84
- Blob = {Blob data}
- Blob = {Blob data}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\CA\Certificates\d2ea461e09eeb661f39dd88f63b2d1b592a7d341
- Blob = {Blob data}
- Blob = {Blob data}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-4}\InprocServer32
- (Default) = %System%\KOALCS~1.OCX
- (Default) = %System%\KOALCS~1.OCX
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{Generated ID-5}\InprocServer32
- (Default) = %System%\KOALCS~1.OCX
- (Default) = %System%\KOALCS~1.OCX
Step 5
Delete this registry key
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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\TypeLib
- {Generated ID-1}
- {Generated ID-1}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface
- {Generated ID-2}
- {Generated ID-2}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
- {Generated ID-4}
- {Generated ID-4}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
- {Generated ID-5}
- {Generated ID-5}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes
- KoalEAClient.CspWrapper.1
- KoalEAClient.CspWrapper.1
- In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
- {Generated ID-6}
- {Generated ID-6}
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\ROOT\Certificates
- b26fa75369d6fd879204d8e67fcc105ef35fcd84
- b26fa75369d6fd879204d8e67fcc105ef35fcd84
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\CA\Certificates
- d2ea461e09eeb661f39dd88f63b2d1b592a7d341
- d2ea461e09eeb661f39dd88f63b2d1b592a7d341
Step 6
Search and delete these files
- %Application Data%\configtools.log
- %Application Data%\configtools.dat
- %System%\KoalCspWrapper.ocx
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as PUA.Win32.Koal.AZ. 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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