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Worm:Win32/Arhost.A
Detected by Microsoft Defender Antivirus
Aliases: TROJ_SWISYN.FE (Trend Micro) Trojan.Win32.Swisyn.acek (Kaspersky) Troj/Ashwho-A (Sophos)
Summary
Worm:Win32/Arhost.A 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 machines. Commonly, worms may spread directly by copying themselves to removable or network drives, or by attempting to exploit particular vulnerabilities on targeted machines. 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.
Manual removal is not recommended for this threat. To detect and remove this threat and other malicious software that may have been installed, run a full-system scan with an up-to-date antivirus product such as Microsoft Security Essentials, or the Microsoft Safety Scanner. For more information about using antivirus software, see http://www.microsoft.com/security/antivirus/av.aspx.
Additional remediation instructions
This threat may make lasting changes to an affected system's configuration that will NOT be restored by detecting and removing this threat. For more information on returning an affected system to its pre-infected state, please see the following information:
Disable Autorun functionality
Worm:Win32/Arhost.A 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: http://support.microsoft.com/kb/967715/
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