---
id: CVE-2026-31628
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  x86/CPU: Fix FPDSS on Zen1

  Zen1's hardware divider can leave, under certain circumstances, partial
  results from previous operations
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  x86/CPU: Fix FPDSS on Zen1

  Zen1's hardware divider can leave, under certain circumstances, partial
  results from previous operations.  Those results can be leaked by
  an…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 3.16.58, < 3.17'
  - 'linux_kernel >= 4.4.144, < 4.5'
  - 'linux_kernel >= 4.9.102, < 4.10'
  - 'linux_kernel >= 4.14.1, < 5.10.253'
  - 'linux_kernel >= 5.11, < 5.15.203'
  - 'linux_kernel >= 5.16, < 6.1.169'
  - 'linux_kernel >= 6.2, < 6.6.135'
  - 'linux_kernel >= 6.7, < 6.12.82'
  - 'linux_kernel >= 6.13, < 6.18.23'
  - 'linux_kernel >= 6.19, < 6.19.13'
  - 'linux_kernel >= 7.0, < 7.0.1'
  - linux_kernel = 4.14
patched:
  - linux_kernel 7.0.1
published: '2026-04-24'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:19:13.707'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-31628'
references:
  - url: 'https://git.kernel.org/stable/c/0548529af20e68c6552817834b766646dd3bd7a7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/1272cfedf4cd1019ddf583917a99b62f2d3645bb'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/546785c719418c6166834a47e372a88f5f7ae893'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/91f02726b2203b71545713ecb7fb006e60a2d66f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ad17f07e95e6e8505e2153e5b391f0d27eacce25'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b731aca06387b195058a9f6449a03b62efa1bd10'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e55d98e7756135f32150b9b8f75d580d0d4b2dd3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/e6af5286efe5a56128b34032572c9ce9ebeccda3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ed7a3a246309ccc807238f1b4f159ee6d37ff9c4'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-019113.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-082556.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-457936.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00129
epssPercentile: 0.0254
ingestedAt: '2026-09-08T15:33:26.990Z'
---

## Overview

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

x86/CPU: Fix FPDSS on Zen1

Zen1's hardware divider can leave, under certain circumstances, partial
results from previous operations.  Those results can be leaked by
another, attacker thread.

Fix that with a chicken bit.

## Affected

- `linux_kernel >= 3.16.58, < 3.17`
- `linux_kernel >= 4.4.144, < 4.5`
- `linux_kernel >= 4.9.102, < 4.10`
- `linux_kernel >= 4.14.1, < 5.10.253`
- `linux_kernel >= 5.11, < 5.15.203`
- `linux_kernel >= 5.16, < 6.1.169`
- `linux_kernel >= 6.2, < 6.6.135`
- `linux_kernel >= 6.7, < 6.12.82`
- `linux_kernel >= 6.13, < 6.18.23`
- `linux_kernel >= 6.19, < 6.19.13`
- `linux_kernel >= 7.0, < 7.0.1`
- `linux_kernel = 4.14`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.0.1`