The recent public announcement of the Meltdown and Spectre critical vulnerabilities in modern processors that could leak passwords and sensitive data are really something that you might want to pay attention to if you are into crypto. Since these hardware vulnerabilities allow programs to steal data which is currently processed on the computer they could potentially lead to passwords and/or other secure data getting leaked and this poses risk for crypto currencies getting stolen from your computer or mobile device. The good news is that various companies have already released operating system and device patches that try to fix or mitigate the potential problems that might be caused by the exploits. So what you should make sure is to update your computer and mobile devices with the latest security patches in order to at least minimize the chances of getting affected by the Meltdown or Spectre exploits.
Meltdown breaks the most fundamental isolation between user applications and the operating system. This attack allows a program to access the memory, and thus also the secrets, of other programs and the operating system. If your computer has a vulnerable processor and runs an unpatched operating system, it is not safe to work with sensitive information without the chance of leaking the information.
Spectre breaks the isolation between different applications. It allows an attacker to trick error-free programs, which follow best practices, into leaking their secrets. In fact, the safety checks of said best practices actually increase the attack surface and may make applications more susceptible to Spectre. Spectre is harder to exploit than Meltdown, but it is also harder to mitigate.
Patching and securing your GPU mining rigs might not be that much of a priority, but computers or mobile devices where you use or store local crypto wallets or passwords for accessing online wallets and/or other crypto related services such as exchanges must be your first priority. Below you can find a link to security information, updates and patches for fixing the problem or at least mitigating the possibility to be exploited using the Meltdown or Spectre, so make sure you check different software and hardware manufacturers recommend that you do and install and patches and updates that they recommend.