AMD thinks that its processors are not impacted by the new SPOILER vulnerability that uses speculative execution to improve the efficiency of memory and cache attacks such as Rowhammer.
To be more exact,
AMD says that its processors are not affected by SPOILER because they do not use "partial address matches above address bit 11" when having to address load conflicts:
We are aware of the report of a new security exploit called SPOILER which can gain access to partial address information during load operations. We believe that our products are not susceptible to this issue because of our unique processor architecture. The SPOILER exploit can gain access to partial address information above address bit 11 during load operations. We believe that our products are not susceptible to this issue because AMD processors do not use partial address matches above address bit 11 when resolving load conflicts.
