Trojan.Dropper is a detection name used by Symantec to identify malicious software programs that drop other malware files onto the compromised computer.
A Trojan.Dropper is a type of Trojan whose purpose is to deliver an enclosed payload onto a destination host computer. A dropper is a means to an end rather than the end itself. In other words, the dropper is usually used at the start or in the early stages of a malware attack.
Once a dropper is executed, its own code is simply to load itself into memory and then extract the malware payload and write it to the file system. It may perform any installation procedures and execute the newly dropped malware. The dropper usually ceases to execute at this point as its primary function has been accomplished.
Droppers are used by malware creators to disguise their malware. They create confusion amongst users by making them look like legitimate applications or well known and trusted files.
They may also perform actions that mislead the user into thinking that nothing untoward is happening on the computer when in fact the Trojan may have already dropped and executed other malicious software.
If a Symantec antivirus product displays a detection alert for this threat, it means the computer is already protected against this threat and the Symantec product will effectively remove this threat from the computer.
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