AMD "Zen 5" RDSEED Bug Threatens Cryptographic Key Generation

AMD has confirmed a hardware defect in the RDSEED instruction on its new Zen 5 processors, cataloged as AMD-SB-7055 and assigned CVE-2025-62626. The company reports that the 16-bit and 32-bit forms of

RDSEED can return zero values, which may be mistakenly interpreted as a successful entropy read. The 64-bit form is unaffected. AMD rates the issue as high severity and suggests short-term software w ...