Use-after-free in Linux kernel - CVE-2026-64459
Published: July 27, 2026
Vulnerability identifier: #VU139473
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-2026-64459
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in the TCP-AO socket destruction logic when processing crafted TCP-AO traffic during connect(). A local user can send crafted network segments and trigger connect() to cause a denial of service.
Exploitation requires the ability to configure TCP_MD5SIG and TCP_AO keys on a socket.
Affected software
Linux kernel
How to mitigate CVE-2026-64459
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3