A recent vulnerability was announced on January 3, 2018, affecting all modern processors. There are two parts to the released vulnerability, and they are as follows:
Meltdown: Allows applications to access operating system memory, providing access to secrets such as passwords. This affects modern Intel chips. There are patches available, however, at this point there seems to be some issues with these patches, causing system instability and slow downs.
Spectre: Breaks the isolation between error-free applications, which allows a malicious application to read memory from another application. This affects all modern chips; Intel, AMD, and ARM.