Use-after-free in Linux kernel - CVE-2026-53259
Published: June 26, 2026
Vulnerability details
The vulnerability allows a local attacker to cause a denial of service.
The vulnerability exists due to a use-after-free in ipv6 anycast address handling in net/ipv6/anycast.c when racing anycast address insertion and device teardown. A local attacker can trigger concurrent anycast join and teardown operations to cause a denial of service.
The issue occurs because a freed ifacaddr6 object can remain linked in the global inet6_acaddr_lst[] hash and later be dereferenced by readers under RCU.
Affected software
Ubuntu
linux (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
How to mitigate CVE-2026-53259
linux (Ubuntu package) - addressed in versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-31.31~24.04.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12, 7.0.0-1012.12~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13