Applications, operating systems, and firmware all need to be updated to defeat Meltdown and protect against Spectre, two attacks that exploit features of high-performance processors to leak information and undermine system security. The computing industry has been scrambling to respond after news of the problem broke early a few days into the new year.
But that patching is proving problematic. The Meltdown protection is revealing bugs or otherwise undesirable behavior in various drivers, and Intel is currently recommending that people cease installing a microcode update it issued to help tackle the Spectre problem. This comes as researchers are digging into the papers describing the issues and getting closer to weaponizing the research to turn it into a practical attack. With the bad guys sure to be doing the same, real-world attacks using this research are sure to follow soon.
Back when initially releasing its Windows patch, Microsoft acknowledged incompatibilities with some anti-virus software. To receive the Meltdown and Spectre fixes, anti-virus software on Windows is required to create a special registry entry indicating that it's compatible. Without this entry, not only are these patches blocked, but so too are all future Windows patches. Most anti-virus vendors should now have compatible versions of their products, but users with stale anti-virus software—expired trials or end-of-lifed products—are at this point much better off removing the third-party software entirely and using the built-in protection in Windows 8.1 and Windows 10.