---
id: CVE-2025-68313
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  x86/CPU/AMD: Add RDSEED fix for Zen5

  There's an issue with RDSEED's 16-bit and 32-bit register output
  variants on Zen5 which return a random value of 0 "at a rate inco…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  x86/CPU/AMD: Add RDSEED fix for Zen5

  There's an issue with RDSEED's 16-bit and 32-bit register output
  variants on Zen5 which return a random value of 0 "at a rate inco…
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'
published: '2025-12-16'
updated: '2026-09-02'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-68313'
references:
  - url: 'https://git.kernel.org/stable/c/36ff93e66d0efc46e39fab536a9feec968daa766'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/607b9fb2ce248cc5b633c5949e0153838992c152'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e980de2ff109dacb6d9d3a77f01b27c467115ecb'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00139
epssPercentile: 0.03651
ingestedAt: '2026-09-02T13:44:41.298Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

x86/CPU/AMD: Add RDSEED fix for Zen5

There's an issue with RDSEED's 16-bit and 32-bit register output
variants on Zen5 which return a random value of 0 "at a rate inconsistent
with randomness while incorrectly signaling success (CF=1)". Search the
web for AMD-SB-7055 for more detail.

Add a fix glue which checks microcode revisions.

  [ bp: Add microcode revisions checking, rewrite. ]

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.