CVE-2025-62626

Published Nov 21, 2025

Last updated 2 months ago

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-62626 affects AMD Zen 5 processors and involves a flaw in the RDSEED instruction, which is used for generating cryptographically secure random numbers. The vulnerability stems from improper handling of insufficient entropy, causing the RDSEED instruction to sometimes return a zero value while incorrectly signaling success. This can lead software to believe it has received a valid random number when it has actually obtained a predictable zero value. The issue impacts the 16-bit and 32-bit forms of the RDSEED instruction. This can result in weak encryption keys, predictable authentication tokens, or compromised security protocols because applications may consume insufficiently random values. A local attacker could potentially influence the values returned by RDSEED, further degrading randomness quality. AMD plans to release microcode patches to address this vulnerability.

Description: Improper handling of insufficient entropy in the AMD CPUs could allow a local attacker to influence the values returned by the RDSEED instruction, potentially resulting in the consumption of insufficiently random values.
Source: psirt@amd.com
NVD status: Awaiting Analysis

Risk scores

CVSS 4.0

Type: Secondary
Base score: 7.2
Impact score: -
Exploitability score: -
Vector string: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Severity: HIGH

Weaknesses

psirt@amd.com: CWE-333

Hype score: Not currently trending

References