Worm:Win32/Rebhip.L is a worm - a self-propagating program that can spread itself from one computer to another. Worms may spread themselves via a variety of different channels in order to compromise new computers. Commonly, worms may spread directly by copying themselves to removable or network drives, or by attempting to exploit particular vulnerabilities on targeted computers. Worms also often attempt to spread via platforms that require user interaction in order to run. They may send themselves as an attachment to an email or an instant message, or send a link to a copy of themselves in the body of a message. In these cases the message needs to be convincing enough to encourage the victim to click on the link or attachment and run or download a copy of the worm.
Installation
When executed, Worm:Win32/Rebhip.L copies itself to %programfiles%\nfs\nfs.exe.
The malware modifies the following registry entries to ensure that its copy executes at each Windows start:
Adds value: "HKLM"
With data: "c:\program files\nfs\nfs.exe"
To subkey: HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
Adds value: "HKCU"
With data: "c:\program files\nfs\nfs.exe"
To subkey: HKCU\Software\Microsoft\windows\currentversion\run
Adds value: "Policies"
With data: "c:\program files\nfs\nfs.exe"
To subkey: HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\Explorer\Run
Adds value: "Policies"
With data: "c:\program files\nfs\nfs.exe"
To subkey: HKCU\Software\Microsoft\Windows\CurrentVersion\policies\Explorer\Run
Adds value: StubPath
With data: "c:\program files\nfs\nfs.exe"
To subkey: hklm\software\microsoft\active setup\installed components\{y54i6vuv-2xke-5upn-fy77-78x11dc6y4xj}
The malware creates the following files on an affected computer:
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c:\documents and settings\administrator\application data\cglogs.dat
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c:\documents and settings\administrator\local settings\temp\uuu.uuu
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c:\documents and settings\administrator\local settings\temp\xx--xx--xx.txt
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c:\documents and settings\administrator\local settings\temp\xxx.xxx
The malware utilizes code injection in order to hinder detection and removal. When Worm:Win32/Rebhip.L executes, it may inject code into running processes, including the following, for example:
Payload
Modifies browser settings
Worm:Win32/Rebhip.L locks the Internet Explorer toolbar by making the following registry modification:
Adds value:
"Locked" With data:
"1"To subkey:
HKCU\Software\Microsoft\Internet Explorer\Toolbar
Contacts remote host
The malware may contact a remote host at gate26.no-ip.biz using port 999. Commonly, malware may contact a remote host for the following purposes:
- To report a new infection to its author
- To receive configuration or other data
- To download and execute arbitrary files (including updates or additional malware)
- To receive instruction from a remote attacker
- To upload data taken from the affected computer
This malware description was produced and published using our automated analysis system's examination of file SHA1 2cdad3581f78396d09183f22b5330a08ed4579eb.