Win32/Daonol is a family of trojans capable of monitoring network traffic, stealing FTP credentials, preventing access to security Web sites, disabling access to system programs, and redirecting Web searches to sites hosting other malware.
Installation
Upon execution, Win32/Daonol drops its DLL file component with a random file name one level up from the current folder. For example, it may drop the file tpqnh.hmq in the default Windows folder if the current folder is the Windows system folder.
It then modifies the system registry so that its dropped file is registered as a Windows NT dynamic-link library for applications, for example:
Adds value: "aux"
With data: "<current folder>\..\tpqnh.hmq"
To subkey: HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Drivers32
where <current folder> is the folder where this trojan is currently running.
Note that by default the value "aux" exists. This registry modification by the trojan replaces the system setting.
Payload
Steals FTP credentials
Win32/Daonol may steal FTP credentials such as FTP server names, user names, and passwords, by hooking WS2_32.dll functions, such as the following, to monitor or modify Internet traffic:
recv
send
connect
WSARecv
WSASend
It then stores the stolen information into a file it creates in the Windows system folder named sqlsodbc.chm. Note that if Windows is installed, a file named sqlsodbc.chm exists by default in the same folder; therefore the presence of this trojan causes the legitimate sqlsodbc.chm file to be overwritten.
The stolen information is then sent to remote servers, such as the following:
195.24.76.250
67.215.237.98
67.215.246.34
94.229.65.172
Prevents access to certain Web sites
Win32/Daonol may prevent access to Web sites containing the following strings in its URL:
Adob
DaonolFix
bleepingcomputer
clamav
mbam
mcafee
miekiemoes
prevx
Disable access to system programs
Win32/Daonol may also disable access via explorer.exe to applications with the following strings:
reged (such as the Registry Editor)
cmd
.bat (any batch file)
.reg (any registry file)
It does this by hooking some functions in kernel32.dll, such as "CreateProcessW".
Redirects Web searches
Win32/Daonol redirects search results from certain sites, such as those containing the following strings, to sites hosting other malware::
msn
live
google
yahoo
Analysis by Jireh Sanico
Take the following steps to help prevent infection on your system:
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Enable a firewall on your computer.
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Get the latest computer updates for all your installed software.
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Use up-to-date antivirus software.
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Use caution when opening attachments and accepting file transfers.
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Use caution when clicking on links to web pages.
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Avoid downloading pirated software.
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Protect yourself against social engineering attacks.
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Use strong passwords.
Enable a firewall on your computer
Use a third-party firewall product or turn on the Microsoft Windows Internet Connection Firewall.
To turn on the Windows Firewall in Windows Vista
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Click Start, and click Control Panel.
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Click Security.
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Click Turn Windows Firewall on or off.
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Select On.
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Click OK.
To turn on the Internet Connection Firewall in Windows XP
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Click Start, and click Control Panel.
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Click Network and Internet Connections. If you do not see Network and Internet Connections, click Switch to Category View.
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Click Change Windows Firewall Settings.
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Select On.
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Click OK.
Get the latest computer updates
Updates help protect your computer from viruses, worms, and other threats as they are discovered. It is important to install updates for all the software that is installed in your computer. These are usually available from vendor websites.
You can use the Automatic Updates feature in Windows to automatically download future Microsoft security updates while your computer is on and connected to the Internet.
To turn on Automatic Updates in Windows Vista
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Click Start, and click Control Panel.
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Click System and Maintainance.
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Click Windows Updates.
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Select a setting. Microsoft recommends selecting Install updates automatically and choose a time that is convenient for you. If you do not choose Automatic, but you choose to be notified when updates are ready, a notification balloon appears when new downloads are available to install. Click the notification balloon to review and install the updates.
To turn on Automatic Updates in Windows XP
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Click Start, and click Control Panel.
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Click System.
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Click Automatic Updates.
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Select a setting. Microsoft recommends selecting Automatic. If you do not choose Automatic, but you choose to be notified when updates are ready, a notification balloon appears when new downloads are available to install. Click the notification balloon to review and install the updates.
Use up-to-date antivirus software
Most antivirus software can detect and prevent infection by known malicious software. To help protect you from infection, you should always run antivirus software that is updated with the latest signature files. Antivirus software is available from several sources. For more information,
see http://www.microsoft.com/protect/computer/viruses/vista.mspx.
Use caution when opening attachments and accepting file transfers
Exercise caution with e-mail and attachments received from unknown sources, or received unexpectedly from known sources. Use extreme caution when accepting file transfers from known or unknown sources.
Use caution when clicking on links to Web pages
Exercise caution with links to web pages that you receive from unknown sources, especially if the links are to a Web page that you are not familiar with, unsure of the destination of, or suspicious of. Malicious software may be installed in your system simply by visiting a Web page with harmful content.
Avoid downloading pirated software
Threats may also be bundled with software and files that are available for download on various torrent sites. Downloading "cracked" or "pirated" software from these sites carries not only the risk of being infected with malware, but is also illegal. For more information, see '
The risks of obtaining and using pirated software'.
Protect yourself from social engineering attacks
While attackers may attempt to exploit vulnerabilities in hardware or software in order to compromise a system, they also attempt to exploit vulnerabilities in human behavior in order to do the same. When an attacker attempts to take advantage of human behavior in order to persuade the affected user to perform an action of the attacker's choice, it is known as 'social engineering'. Essentially, social engineering is an attack against the human interface of the targeted system. For more information, see '
What is social engineering?'.
Use Strong Passwords
Attackers may try to gain access to your Windows account by guessing your password. It is therefore important that you use a strong password – one that cannot be easily guessed by an attacker. A strong password is one that has at least 8 characters, and combines letters, numbers, and symbols. For more information, see
http://www.microsoft.com/protect/yourself/password/create.mspx.