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Worm:Win32/Nenebra.A
Detected by Microsoft Defender Antivirus
Aliases: Win-Trojan/Cosmu.212480 (AhnLab) Trojan.Win32.Cosmu.xxs (Kaspersky) Trojan.Cosmu.CYL (VirusBuster) Win32/AutoRun.Delf.HF (ESET) Trojan.Win32.Cosmu (Ikarus)
Summary
Worm:Win32/Nenebra.A is the detection for a worm that spreads through fixed and removable drives. It connects to remote FTP sites to download and execute additional malware components.
To detect and remove this threat and other malicious software that may be installed in your computer, run a full-system scan with an up-to-date antivirus product such as the following:
For more information on antivirus software, see http://www.microsoft.com/windows/antivirus-partners/.
Removing a program exception
This threat may add a malware program to the Windows Firewall exception list. To remove the program exception, follow these steps:
For Windows 7:
1) Click Start, select Control Panel, then System and Security.
2) Select Windows Firewall.
3) On the left-hand menu, select Allow a program through Windows Firewall. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
4) Click Change Settings. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
5) Select "Windows Update" from the list of allowed programs and features. Click Remove.
6) Click OK.
2) Select Windows Firewall.
3) On the left-hand menu, select Allow a program through Windows Firewall. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
4) Click Change Settings. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
5) Select "Windows Update" from the list of allowed programs and features. Click Remove.
6) Click OK.
For Windows Vista:
1) Click Start, select Control Panel, then Security Center.
2) On the left-hand menu, select Windows Firewall.
3) On the left-hand menu, select Allow a program through Windows Firewall. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
4) Select "Windows Update" from the list of allowed programs and features. Click Delete.
5) Click OK.
2) On the left-hand menu, select Windows Firewall.
3) On the left-hand menu, select Allow a program through Windows Firewall. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
4) Select "Windows Update" from the list of allowed programs and features. Click Delete.
5) Click OK.
For Windows XP:
1) Use an administrator account to log on.
2) Click Start, select Run, type wscui.cpl, and then click OK.
3) In Windows Security Center, click Windows Firewall.
4) On the Exceptions tab, click "Windows Update" and then click Delete.
5) Click OK.
2) Click Start, select Run, type wscui.cpl, and then click OK.
3) In Windows Security Center, click Windows Firewall.
4) On the Exceptions tab, click "Windows Update" and then click Delete.
5) Click OK.
Disable Autorun functionality
This threat attempts to spread via removable drives on computers that support Autorun functionality. This is a particularly common method of spreading for many current malware families. For information on disabling Autorun functionality, please see the following article:
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