The news will apparently get worse before it gets any better for Intel, as the company updated their security recommendations for the Spectre/Meltdown patches for affected CPUs to address post-patch system restart issues. Specifically, Intel notes that issues may be introduced in some configurations with the current patches, though the company does not recommend discontinued use of such updates:

" Intel recommends that these partners, at their discretion, continue development and release of updates with existing microcode to provide protection against these exploits, understanding that the current versions may introduce issues such as reboot in some configurations".

Image credit: HotHardware

The recommendation section of the security bulletin, updated yesterday (January 17, 2018), is reproduced below:

Intel has made significant progress in our investigation into the customer reboot sightings that we confirmed publicly last week

Intel has reproduced these issues internally and has developed a test method that allows us to do so in a predictable manner

Initial sightings were reported on Broadwell and Haswell based platforms in some configurations. During due diligence we determined that similar behavior occurs on other products including Ivy Bridge, Sandy Bridge, Skylake, and Kaby Lake based platforms in some configurations

We are working toward root cause

While our root cause analysis continues, we will start making beta microcode updates available to OEMs, Cloud service providers, system manufacturers and Software vendors next week for internal evaluation purposes

In all cases, the existing and any new beta microcode updates continue to provide protection against the exploit (CVE-2017-5715) also known as “Spectre Variant 2”

Variants 1 (Spectre) and Variant 3 (Meltdown) continue to be mitigated through system software changes from operating system and virtual machine vendors

As we gather feedback from our customers we will continue to provide updates that improve upon performance and usability Intel recommendations to OEMs, Cloud service providers, system manufacturers and software vendors Intel recommends that these partners maintain availability of existing microcode updates already released to end users. Intel does not recommend pulling back any updates already made available to end users

to end users. Intel does recommend pulling back any updates already made available to end users NEW – Intel recommends that these partners, at their discretion, continue development and release of updates with existing microcode to provide protection against these exploits, understanding that the current versions may introduce issues such as reboot in some configurations

Intel recommends that these partners, at their discretion, continue development and release of updates with existing microcode to provide protection against these exploits, understanding that the current versions may introduce issues such as reboot in some configurations NEW – We further recommend that OEMs, Cloud service providers, system manufacturers and software vendors begin evaluation of Intel beta microcode update releases in anticipation of definitive root cause and subsequent production releases suitable for end users Intel recommendations to end users Following good security practices that protect against malware in general will also help protect against possible exploitation until updates can be applied

For PCs and Data Center infrastructure, Intel recommends that patches be applied as soon as they are available from your system manufacturer, and software vendors

For data center infrastructure, Intel additionally recommends that IT administrators evaluate potential impacts from the reboot issue and make decisions based on the security profile of the infrastructure Intel has worked with operating system vendors, equipment manufacturers, and other ecosystem partners to develop software updates that can help protect systems from these methods. End users and systems administrators should check with their operating system vendors and apply any available updates as soon as practical.

The full list of affected processors from Intel's security bulletin follows:

Intel® Core™ i3 processor (45nm and 32nm)

Intel® Core™ i5 processor (45nm and 32nm)

Intel® Core™ i7 processor (45nm and 32nm)

Intel® Core™ M processor family (45nm and 32nm)

2nd generation Intel® Core™ processors

3rd generation Intel® Core™ processors

4th generation Intel® Core™ processors

5th generation Intel® Core™ processors

6th generation Intel® Core™ processors

7th generation Intel® Core™ processors

8th generation Intel® Core™ processors

Intel® Core™ X-series Processor Family for Intel® X99 platforms

Intel® Core™ X-series Processor Family for Intel® X299 platforms

Intel® Xeon® processor 3400 series

Intel® Xeon® processor 3600 series

Intel® Xeon® processor 5500 series

Intel® Xeon® processor 5600 series

Intel® Xeon® processor 6500 series

Intel® Xeon® processor 7500 series

Intel® Xeon® Processor E3 Family

Intel® Xeon® Processor E3 v2 Family

Intel® Xeon® Processor E3 v3 Family

Intel® Xeon® Processor E3 v4 Family

Intel® Xeon® Processor E3 v5 Family

Intel® Xeon® Processor E3 v6 Family

Intel® Xeon® Processor E5 Family

Intel® Xeon® Processor E5 v2 Family

Intel® Xeon® Processor E5 v3 Family

Intel® Xeon® Processor E5 v4 Family

Intel® Xeon® Processor E7 Family

Intel® Xeon® Processor E7 v2 Family

Intel® Xeon® Processor E7 v3 Family

Intel® Xeon® Processor E7 v4 Family

Intel® Xeon® Processor Scalable Family

Intel® Xeon Phi™ Processor 3200, 5200, 7200 Series

Intel® Atom™ Processor C Series

Intel® Atom™ Processor E Series

Intel® Atom™ Processor A Series

Intel® Atom™ Processor x3 Series

Intel® Atom™ Processor Z Series

Intel® Celeron® Processor J Series

Intel® Celeron® Processor N Series

Intel® Pentium® Processor J Series

Intel® Pentium® Processor N Series

We await further updates and developments from Intel, system integrators, and motherboard partners.