Since January, Intel has been working on mitigating the impact of the Spectre vulnerability by releasing microcode updates for past chips. Intel CPUs dating back an entire decade are prone to Spectre, so the company started at the top, and began working its way down towards older generations. Patches for Intel CPUs released between 2007 and 2009 were in the planning stages according to Intel's update sheet, but they appear to have been canceled for the time being.
In the March edition of Intel's Microcode update guidance, it was shown that updates for Bloomfield, Clarksfield, Harpertown, Jasper Forest, Penryn, Wolfdale and Yorkfield CPUs were either in pre-beta or planning stages. Now, in the April update of the microcode update guidance sheet, production has halted on these CPUs.
While old, these architectures cover a number of prominent processors, including the Core i7-920, 940 and 965 Extreme Edition. Other chips include the Core 2, Core 2 Duo and Core 2 Quad series, as well as a chunk of older Xeon processors.
Intel explains that patches for these processors were halted for several reasons. This includes lack of commercially available system software support, essentially meaning that Intel may not be able to get partners on board to push out updates to systems nearing a decade old.
Aside from that, Intel says that there are some “micro-architectural characteristics that preclude a practical implementation” to mitigate Spectre Variant 2. Finally, Intel says that based on customer feedback, it has learned that many systems still using these older processors are ‘closed systems', which would be less likely to encounter these vulnerabilities.
KitGuru Says: Most consumers will have moved on from these products at this point in time, though there may still be some enterprise customers utilising Intel's older processors. It looks like for one reason or another, those customers won't be getting a Spectre microcode update for the time being.