BKDR_DEFSEL.NIN
Backdoor:Win32/Defsel.B (Microsoft); RDN/Generic.grp (McAfee); Trojan.Gen (Symantec); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse Generic38.BNOE (AVG)
Windows
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
322,179 bytes
EXE
No
12 Jun 2017
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.
Other System Modifications
This Backdoor modifies the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Dfrg\BootOptimizeFunction
LcnStartLocation = "1463841"
(Note: The default value data of the said registry entry is 0.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Dfrg\BootOptimizeFunction
LcnEndLocation = "1665343"
(Note: The default value data of the said registry entry is 0.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Dfrg\BootOptimizeFunction
OptimizeError = "Insufficient free space"
(Note: The default value data of the said registry entry is Not Run.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Dfrg\BootOptimizeFunction
OptimizeComplete = "No"
(Note: The default value data of the said registry entry is No.)
Other Details
This Backdoor connects to the following possibly malicious URL:
- {BLOCKED}.157.124
This report is generated via an automated analysis system.
SOLUTION
9.8
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 2
Restore these modified registry values
Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Dfrg\BootOptimizeFunction
- From: LcnStartLocation = "1463841"
To: LcnStartLocation = ""0""
- From: LcnStartLocation = "1463841"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Dfrg\BootOptimizeFunction
- From: LcnEndLocation = "1665343"
To: LcnEndLocation = ""0""
- From: LcnEndLocation = "1665343"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Dfrg\BootOptimizeFunction
- From: OptimizeError = "Insufficient free space"
To: OptimizeError = ""Not Run""
- From: OptimizeError = "Insufficient free space"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Dfrg\BootOptimizeFunction
- From: OptimizeComplete = "No"
To: OptimizeComplete = ""No""
- From: OptimizeComplete = "No"
Step 3
Scan your computer with your Trend Micro product to delete files detected as BKDR_DEFSEL.NIN. 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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