---
cve: "CVE-2026-43040"
severity: "LOW"
cvss: 3.1
epss: "12%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-05-01 15:16:50"
tags: [cve, security, low]
source: tsecurity.de CVE-Dossier
exported: "2026-09-11T16:06:29+02:00"
---

# CVE-2026-43040

> 3.1 LOW

## Beschreibung

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

net: ipv6: ndisc: fix ndisc_ra_useropt to initialize nduseropt_padX fields to zero to prevent an info-leak

When processing Router Advertisements with user options the kernel
builds an RTM_NEWNDUSEROPT netlink message. The nduseroptmsg struct
has three padding fields that are never zeroed and can leak kernel data

The fix is simple, just zeroes the padding fields.

## Patch verfügbar (OSV)

- Kernel ≥ 5.10.253
- Kernel ≥ 5.15.203
- Kernel ≥ 6.1.168
- Kernel ≥ 6.6.134
- Kernel ≥ 6.12.81
- Kernel ≥ 6.18.22
- Kernel ≥ 6.19.12

## Referenzen

- <https://git.kernel.org/stable/c/1da9023f6b071a38e5430ffbce4b70b2b1ac4f9c>
- <https://git.kernel.org/stable/c/2fe4d0ba690a69ad6ae9f7ab9bdc96e02610b648>
- <https://git.kernel.org/stable/c/11d7fe97421cfc81549940c20ed5ac9472d6db05>
- <https://git.kernel.org/stable/c/7f56d87e527bb5a13c3e8b0d5840cb6332822f6d>
- <https://git.kernel.org/stable/c/4f810c686fde509d1cdaa706322d9d2531f8f1a4>
- <https://git.kernel.org/stable/c/b485eef3d97b7aae55ce669b6de555ec81f3d21c>
- <https://git.kernel.org/stable/c/ef3645606e4a635d5062a492f22b7f490852ee67>
- <https://git.kernel.org/stable/c/ae05340ccaa9d347fe85415609e075545bec589f>
- <https://cert-portal.siemens.com/productcert/html/ssa-019113.html>
- <https://cert-portal.siemens.com/productcert/html/ssa-082556.html>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-43040) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_