Users who avoid suspicious email attachments, download applications solely from reputable platforms like Microsoft or Steam, and select browser add-ons based on high ratings and popularity may still face malware threats on their computers.
The explanation lies in cybercriminals infiltrating established programs to distribute harmful updates to unaware individuals.
Such tactics were once uncommon. The 2017 breach of the popular PC tool CCleaner gained widespread attention partly due to its rarity. Until relatively recently, reports of these incidents remained sporadic.
Advancements in artificial intelligence have intensified cybersecurity challenges, enabling malicious entities to accelerate and expand their operations. In earlier times, the primary focus was on browser extensions that fulfilled their stated functions while secretly engaging in illicit behaviors. These ranged from relatively benign issues, such as the redirection of affiliate marketing links, to severe risks like the theft of login details for email or financial accounts, or direct malware infections.
Today, a wider array of applications is affected. For instance, several cases of malware appearing in games obtained from Steam surfaced in 2025. Long-established tools, including Notepad++, have also inadvertently delivered corrupted updates to users' systems.
The Notepad++ incident involved a supply-chain compromise, where intruders exploited an external software component to propagate malware via the application.
Cybercriminals typically employ a few standard approaches to infiltrate genuine software. They might breach the developer's accounts by stealing or brute-forcing passwords. Alternatively, they could purchase unauthorized entry from the creators themselves. A further technique involves targeting utilities or services that developers depend on, which is precisely what occurred with Notepad++ through its vulnerable third-party updater.
As a result, antivirus protection remains essential for online safety, regardless of cautious user habits. It functions like an advanced defense mechanism, detecting potential breaches and preventing malware from executing its payload.
Those who habitually turn off antivirus software—or significant features thereof—due to concerns over system slowdown should reconsider. Solutions such as Windows Security, along with established options from providers like Norton and McAfee, have evolved considerably from the era of early personal computing. Personal assessments confirm that their influence on everyday performance is negligible.