BKDR_CAPCHAW.SAG
Backdoor:Win32/Caphaw.A (Microsoft), Trojan.Shylock (Symantec), Backdoor.Win32.Caphaw (Sunbelt)
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This backdoor modifies the Internet Explorer Zone Settings.
It deletes itself after execution.
TECHNICAL DETAILS
Other System Modifications
This backdoor adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
NoProtectedModeBanner = "1"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
DisableCachingOfSSLPages = "0"
Web Browser Home Page and Search Page Modification
This backdoor modifies the Internet Explorer Zone Settings.
Other Details
This backdoor connects to the following possibly malicious URL:
- {BLOCKED}.[BLOCKED}.117.73
- {BLOCKED}.{BLOCKED}.159.106
- {BLOCKED}.{BLOCKED}.23.43
- {BLOCKED}.{BLOCKED}.100.140
- {BLOCKED}.{BLOCKED}.102.15
- {BLOCKED}.{BLOCKED}.66.132
- {BLOCKED}.{BLOCKED}.85.16
- {BLOCKED}q.cc
- {BLOCKED}o.su
It deletes itself after execution.
SOLUTION
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
Restart in Safe Mode
Step 3
Reset Internet security settings
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_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
- NoProtectedModeBanner = "1"
- NoProtectedModeBanner = "1"
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
- DisableCachingOfSSLPages = "0"
- DisableCachingOfSSLPages = "0"
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_CAPCHAW.SAG. 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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