Trojan.Downloader

Trojan.Downloader is a label that's used to identify Trojans with the primary purpose of downloading other files onto your computer – usually without your permission. However, Trojan.Downloader variants may also have other functions, such as launching files that Trojan.Downloader downloads, installing PC threats or even disabling your computer's security. Since a Trojan.Downloader infection is as dangerous as files that Trojan.Downloader downloads, and since these can include highly-invasive PC threats like rootkits and spyware, SpywareRemove.com malware analysts discourage attempts to ignore Trojan.Downloader or remove Trojan.Downloader without help from anti-malware products. Symptoms of a Trojan.Downloader attack may not be very visible, although, in most cases, Trojan.Downloader will make some kind of visible changes to your firewall or network settings.

Deadly Downloads from a Downloader That's Happy to Avoid Asking for Permission

Trojan.Downloader shares a somewhat-overlapping definition with Trojan.Dropper, since both are used to download and install other types of harmful files on an infected PC. Trojan.Downloader is distinguished from a Trojan.Dropper infection by dint of the fact that Trojan.Downloader is typically-used to refer to an active component of a multi-component infection while a Trojan.Dropper label is often reserved for separate Trojans that install an independent PC threat without coordinating their actions further. A Trojan.Dropper will often try to disguise itself in the form of a desirable file or program and will install an enclosed PC threat, while Trojan.Downloader will commonly-attempt to conceal its presence altogether while Trojan.Downloader downloads PC threats from remote servers. However, the two terms are sometimes used in a semi-interchangeable fashion.

Typical behavior from Trojan.Downloader that SpywareRemove.com malware experts have noted includes:

• Attempts to bypass the local firewall and other types of network security. Trojan.Downloader may do this by creating visible setting changes (such as by adding its program to your Windows Firewall's list of exceptions), although this is not always the case.
• Contact with remote servers that host the files that Trojan.Downloader is instructed to download (and, typically, install). In some cases, Trojan.Downloader may also be configured to send out information – such as information that identifies your PC for further attacks.
• The installation of other PC threats. This often includes rogue security programs, browser-redirecting Trojans and spyware. However, SpywareRemove.com malware research team also notes that Trojan.Downloader can be told to download other components for an attack that aren't considered to be independent PC threats in and of themselves.

How to Find Trojan.Downloader Before Its Payload Makes You Pay

Variants of Trojan.Downloader may display separate files or they may be injected into normal Windows files. You may be able to notice Trojan.Downloader by its unusual usage of RAM and other system resources, which can be observed from Task Manager – regardless of whether Trojan.Downloader is using an independent memory process or riding on the back of a native process. However, you shouldn't attempt to remove Trojan.Downloader without an appropriate anti-malware program, since many variants of Trojan.Downloader possess self-defensive functions and since Trojan.Downloader will often come with other PC threats.

Examples of widely-distributed types of Trojan.Downloader-based PC threats include Trojan-Downloader.Win32.Banload.bqmv, Trojan-Downloader.Win32.VB.aoff, Win-Trojan/Downloader.141317, Trojan-Downloader.Win32.Bancos and Trojan-Downloader.Apher. SpywareRemove.com malware analysts also noted pointedly that many of these Trojan.Downloader examples pull double-duty in the form of banking Trojans – an example of the multiple levels of functionality that are common to many types of Trojans.

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