Use-after-free in Linux kernel - CVE-2026-53259

 

Use-after-free in Linux kernel - CVE-2026-53259

Published: June 26, 2026


Vulnerability identifier: #VU135499
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-53259
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability: No public exploit available

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

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

How to mitigate CVE-2026-53259

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
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

External References

Related Security Bulletins