We are constantly reading of targeted attacks and personal home computers being under the threat of malware infection. While these occurrences may sound like a single event, in reality, a malware infection encapsulates multiple stages that have been developed and perfected over the years to ensure success, persistence, survival and invisibility.

Once a device is compromised by a dropper and a downloader, the payload can be anything from financial malware to remote access tools (RATs), ransomware, spamming software or others.

About the Malware Infection Process

A critical step of the malware infection process is the dropper. The dropper is the spearhead of the malware infection; it is a small piece of software that clears the path for the payload. Droppers will use multiple techniques to evade detection by endpoint security products such as antivirus programs, corporate security products such as sandboxes and other evasion tools used by researchers.

As those security researchers perfected their methods of detecting and analyzing malware, the malware authors realized they needed to invest time and effort into protecting their malicious programs from detection tools. This includes developing techniques to evade virtual environments, avoid malware infection of systems that have a research profile — the existence of reverse engineering tools and communication analysis is just one example — and even attempt to trick sandbox solutions with elaborate sleep techniques, human interaction detection and log file overloading.

Once the dropper completes its part, a payload can be safely delivered to the targeted system. This may include a downloader that will allow the attacker to download any piece of malware to this device in the future. This enables cybercriminals to also sell such controlled devices via a pay-per-infection method.

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Finding Treatment for Infections

There is much more to the malware infection process, including preparation stages such as creating an infection point and using spammers to lure victims. Those entryways can be drive-by infection points, emails with weaponized content and more. There’s plenty happening post-infection as well, including multiple modules that can manipulate online sessions, allow remote access and perform an analysis of the infected device.

As security solutions keep getting more sophisticated and aggressive in their detection and remediation capabilities, we can only expect the droppers, downloaders, packers and other modules in the malware infection process to evolve and adjust.

For more information on the evolving malware ecosystem, watch the video below:

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