Cidra Trojan has a lot of variants, that's why there's no guarantee that the latest variants will be detected by your antiviral system. This parasite acts like a TrojanProxy, which means that the infected machine may simply become a spamming tool. Spammers often need more machines for their activities, that's why they are really interested in infecting computers with parasites of this type.
TrojanProxy.Win32.CidraProxy-CidraTrojan.Downloader.IupdTrojan.JFour
usb_d.exe