Over time, technology has improved. It's gotten smarter, smaller, faster, and just generally better at the things it tries to accomplish. However, there is a caveat to this rapid development. Our growing dependence on technology means that, as time goes on, our private lives become more and more connected to the computer. This, unfortunately, opens up a whole world of problems when it comes to security. For example:
Keystroke logging (often called keylogging for short) is the practice of keeping track of everything a user types on a keyboard. This is accomplished with the help of keystroke loggers (keyloggers), which can either be in the form of hardware or software.(1)
Although this kind of attack is nothing new, bearing many resemblances to things like wiretapping, keylogging is much more revealing. While wiretaps only track whatever a user decides to say on the phone, keyloggers track anything that a user types on a computer, which is much less separable from ourselves than phones are.
An encryption backdoor, often shortened to simply backdoor, is an entrance to a computer system that allows complete, unrestricted access to all data stored within.(2) These can be placed in the software's code accidentally, although backdoors are most notorious for being placed in software intentionally with the purpose of use by government agencies like the NSA and CIA.(3)
This is somewhat similar to a keylogger in its method of extracting data, although it does differ in one major way - accessibility. While a keylogger is attached to a specific computer, backdoors are attached to software that anyone can use. This spreads out the damage quite a bit. Backdoors are also much less detectable - unless a software is open-source, it is often impossible to know whether something contains an encryption backdoor or not. This makes this much more dangerous, and can ruin the lives of millions of individuals when it comes to anything with credit cards involved.
Zero-days (also known as 0-days) are vulnerabilities that are so new/obscure that they are completely unknown to anyone who would want to mitigate them. This kind of vulnerability is called a "zero-day" because, as there is no real knowledge of the exploit until it occurs, there has been zero days for the bug to be patched, as well as a 0% probability that it will not work on a user of the vulnerable system.(4)
The danger of attacks using zero-days is enormous: as there is literally no protection against the bug, any attack on a system will succeed. This makes these attacks particularly devastating, with hundreds of thousands of victims and widespread media coverage. One example that comes to mind is Stuxnet, a cyberweapon by America and Israel that utilised 4 seperate 0-days that targeted common control systems in manufacturing and ended up causing noticeable damage to Iran's nuclear program, with around 1/5 of their centrifuges being damaged in the attack.(5)
In conclusion, there are many dangerous and pervasive vulnerabilites that can be exploited on every person's computer, with many of these vulnerabilites sprouting from a want for more information. Except for staying aware about the security of your devices, there is really nothing that can be done - all of the vulnerabilites presented here are virtually undetectable and nearly impossible to mitigate. It's unfortunate, yes, but it's true.