---
id: CVE-2026-31483
title: 's390/syscalls: Add spectre boundary for syscall dispatch table'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  s390/syscalls: Add spectre boundary for syscall dispatch table

  The s390 syscall number is directly controlled by userspace, but does
  not have an array_index_nospec() b…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d <
    3c3b97064764899c39a0abbd35a6caa031e70333
  - >-
    Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d <
    1cb9c7bc9025c637564fabc7fcc3c9343949e310
  - >-
    Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d <
    7a5260fbc6e79a1595328ec5c6aa3f937504a1f0
  - >-
    Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d <
    f8c444b918d639e1f9a621ee20fe481c1d10dfc4
  - >-
    Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d <
    87776f02449e3bded95b2ccbd6b012e9ae64e6f3
  - >-
    Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d <
    4d05dd18d867d58c6952a3bc260d244899da7256
  - >-
    Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d <
    48b8814e25d073dd84daf990a879a820bad2bcbd
  - Linux 5.12
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T21:34:44.578683Z'
published: '2026-04-22'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T21:45:01.265Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-31483'
references:
  - url: 'https://git.kernel.org/stable/c/3c3b97064764899c39a0abbd35a6caa031e70333'
  - url: 'https://git.kernel.org/stable/c/1cb9c7bc9025c637564fabc7fcc3c9343949e310'
  - url: 'https://git.kernel.org/stable/c/7a5260fbc6e79a1595328ec5c6aa3f937504a1f0'
  - url: 'https://git.kernel.org/stable/c/f8c444b918d639e1f9a621ee20fe481c1d10dfc4'
  - url: 'https://git.kernel.org/stable/c/87776f02449e3bded95b2ccbd6b012e9ae64e6f3'
  - url: 'https://git.kernel.org/stable/c/4d05dd18d867d58c6952a3bc260d244899da7256'
  - url: 'https://git.kernel.org/stable/c/48b8814e25d073dd84daf990a879a820bad2bcbd'
tags:
  - cve.org
epss: 0.00123
epssPercentile: 0.02031
ingestedAt: '2026-11-05T22:38:32.150Z'
---

## Overview

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

s390/syscalls: Add spectre boundary for syscall dispatch table

The s390 syscall number is directly controlled by userspace, but does
not have an array_index_nospec() boundary to prevent access past the
syscall function pointer tables.

## Affected

- `Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d < 3c3b97064764899c39a0abbd35a6caa031e70333`
- `Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d < 1cb9c7bc9025c637564fabc7fcc3c9343949e310`
- `Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d < 7a5260fbc6e79a1595328ec5c6aa3f937504a1f0`
- `Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d < f8c444b918d639e1f9a621ee20fe481c1d10dfc4`
- `Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d < 87776f02449e3bded95b2ccbd6b012e9ae64e6f3`
- `Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d < 4d05dd18d867d58c6952a3bc260d244899da7256`
- `Linux >= 56e62a73702836017564eaacd5212e4d0fa1c01d < 48b8814e25d073dd84daf990a879a820bad2bcbd`
- `Linux 5.12`

## Remediation

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