What you need to do about newly discovered computer chip flaws
Meltdown is a flaw that affects laptops, desktop computers and internet servers with Intel chips and could let hackers steal data, such as passwords saved in Web browsers.
Microsoft Corp, Apple Inc and Linux, the three major operating systems, are all issuing updates, though the Apple and Microsoft have not said precisely when.
Spectre affects chips in smartphones and tablets, as well as computer chips from Intel and Advanced Micro Devices Inc.
Hackers can trick apps into leaking sensitive information.
Alphabet Inc's Google said Android phones with the most recent security updates are protected, and users of popular web services like Gmail are also safe.
Chromebook users on older versions will need to install an update whose release date has not been set. Chrome web browser users are expected to receive a patch January 23.
Researchers say an update is in the work for Apple laptops and desktops, but it is not yet clear whether the company's iPhones and iPads are at risk.
Major cloud services aimed at business customers - including Amazon Web Services, Google Cloud Platform and Microsoft Azure - say they have already patched most of their services and will fix the rest soon.