Improper access control in Linux kernel - CVE-2026-72051
Published: August 16, 2026
Vulnerability details
The vulnerability allows a local privileged user to modify tunnel configuration across network namespaces.
The vulnerability exists due to improper access control in ip6_tnl_changelink() when handling changelink requests for IPv6 tunnel devices across network namespaces. A local privileged user can send a crafted netlink changelink request to modify tunnel configuration across network namespaces.
The issue occurs when the device network namespace differs from the tunnel link network namespace.
Affected software
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
How to mitigate CVE-2026-72051
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
External References
- https://git.kernel.org/stable/c/234cd54fc500f69db43e37de38603da617fbbeea
- https://git.kernel.org/stable/c/2496fa0b7d180b3ad356b514e7ff93bb14e6140a
- https://git.kernel.org/stable/c/2636d061bc237a2446a146e42dcc6563acfa7432
- https://git.kernel.org/stable/c/7f68f7928484f463a5bc0d50e6fdd8d16f55a5aa
- https://git.kernel.org/stable/c/d4bcc202a3530c856e1cb183384bc9cc8fddab22