Intel halts development of Specter microcode for legacy processors

Intel has stopped developing microcode to counter the second variant of the Specter vulnerability on quite a few old processors. CPUs from the Bloomfield family, among others, no longer receive patches.

Intel released a new version of its Microcode Update Guidance this week, revealing that patch development for several old CPUs has stopped. That was noticed by TechPowerUp.

The Bloomfield family, among others, will not receive a new microcode. Intel made these processors between 2008 and 2011, and that series included the Core i7-920. Microcode development for the Clarksfield family of mobile CPUs has also ceased. These were made between 2009 and 2012. Other families where Intel says they have discontinued the patches are Harpertown, Jasper Forest, Penryn, Wolfdale and Yorkfield and their Xeon variants. For example, the Penryn and Wolfdale families include the Core 2 Duo and Core 2 Quad processors.

In the previous version of the document, the status of many of these CPU families was ‘planning’ or ‘pre-beta’. The fine print of the new list explains why Intel no longer makes patches for the old processors. The manufacturer states that these include ‘characteristics in the microarchitecture’ that stand in the way of a practical implementation. Intel also cites limited software support for such systems as the reason. Intel also states that many of its customers use systems with the CPUs in question as ‘closed systems’ and therefore expect to run less risk.