4.3Medium
Ibm I
CVE-2026-17255
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.
What this means for your business
- It affects Ibm I. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it from inside the same network, without a login, and without anyone at your company clicking anything.
What to do
- 1Check whether your company or your suppliers run Ibm I, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L- Weakness
- CWE-787
- Assigned by
- psirt@us.ibm.com
Dates
- Published
- 2026-09-04
- Last modified
- 2026-09-10
- Sources
- NVD
Affected products
- Ibm I7.3, 7.4, 7.5, 7.6
As listed in the NVD configuration data. Not a statement about your estate.