---
id: CVE-2026-17255
title: >-
  IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to cause a denial
  of service due to improper validation of the prefix length in ICMPv6 Router
  Advertisements.
summary: >-
  IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to cause a denial
  of service due to improper validation of the prefix length in ICMPv6 Router
  Advertisements.
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-787
vendor: ibm
product: i
affected:
  - i = 7.3
  - i = 7.4
  - i = 7.5
  - i = 7.6
published: '2026-09-04'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T16:17:08.337'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-17255'
references:
  - url: 'https://www.ibm.com/support/pages/node/7286093'
    label: psirt@us.ibm.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-09T18:27:28.122624Z'
epss: 0.00405
epssPercentile: 0.31902
ingestedAt: '2026-09-08T15:33:26.962Z'
---

## Overview

IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to cause a denial of service due to improper validation of the prefix length in ICMPv6 Router Advertisements.

## Affected

- `i = 7.3`
- `i = 7.4`
- `i = 7.5`
- `i = 7.6`

## Remediation

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