SB2026081287 - Improper access control in Linux kernel net vxlan driver



SB2026081287 - Improper access control in Linux kernel net vxlan driver

Published: August 12, 2026

Security Bulletin ID SB2026081287
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Data manipulation

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Improper access control (CVE-ID: CVE-2026-68432)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local privileged user to modify VXLAN device configuration across network namespaces.

The vulnerability exists due to improper access control in vxlan_changelink() when handling changelink requests for a VXLAN device whose underlay network namespace differs from the device network namespace. A local privileged user can send a crafted changelink request to modify VXLAN device configuration across network namespaces.

The issue occurs when the caller has CAP_NET_ADMIN in the device network namespace but not in the VXLAN underlay network namespace.


Remediation

Install update from vendor's website.