Careful Where You Upload – New Ransomware Threat

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While cybersecurity-savvy internet users know they should avoid clicking on links that may download unknown files onto their devices, a new emerging threat can endanger file uploaders, too.

Today’s browsers are much more powerful than earlier generations, almost operating systems themselves with how they can run software programs and encrypt files. When these capabilities are combined with the browser’s access to the host computer’s files (even files on the cloud, shared folders, or external drives), it creates a new opportunity for malicious actors to enact ransomware attacks.

According to Techxplore, when a user tries uploading certain files to an innocent-looking website, any hackers who control the website can access the files on their computer through the browser, accessing the relevant folder and all its subfolders. The hackers could then encrypt the files in the system and demand a ransom payment to decrypt them.

Such ransomware attacks are a growing problem, with organizations paying over 1.1 billion dollars in ransomware payments in 2023 alone. It is no surprise then that ransomware is today’s biggest battleground between hackers and security specialists.

A team of cybersecurity researchers at Florida International University has reportedly been investigating this new type of potential ransomware for the past few years, focusing on how modern web browsers can be weaponized by hackers to create novel forms of ransomware. They even published a paper showing how damaging this emerging ransomware strain is, and how easy it is to design.

The researchers proposed three different approaches to defend against this new type of ransomware that operate at different levels and complement one another. The first approach temporarily stops a web application from detecting encrypted user files, the second approach monitors the activity of the web application on the user’s computer to identify ransomware-like patterns, and the third approach introduces a new permission dialog box to inform users about the risks and implications associated with allowing web applications to access their computer’s file system.

To conclude, you should always be careful when dealing with accessing your computer files, whether you are downloading or uploading them.