According to Wikipedia, AMD CPU's are just as vulnerable to Spectre variant 1 and 2 as is Intel. The confusion that AMD was not vulnerable to variant 2 was due to a mistake made by AMD and later corrected by them 9 days later after verifying they were also vulnerable to variant 2.

AMD originally acknowledged vulnerability to one of the Spectre variants (GPZ variant 1), but stated that vulnerability to another (GPZ variant 2) had not been demonstrated on AMD processors, claiming it posed a "near zero risk of exploitation" due to differences in AMD architecture. In an update nine days later, AMD said that "GPZ Variant 2…is applicable to AMD processors" and defined upcoming steps to mitigate the threat. Several sources took AMD's news of the vulnerability to GPZ variant 2 as a change from AMD's prior claim, though AMD maintained that their position had not changed.