Use-after-free in Linux kernel - CVE-2026-80926

Vulnerability identifier: #VU149464

CSH Severity: Low

CVSS v4: 0 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-80926

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote user to trigger a use-after-free.

The vulnerability exists due to use-after-free in the ksmbd oplock break notification path when processing an oplock break concurrently with durable-handle connection teardown. A remote user can hold a durable batch oplock and trigger an oplock break during connection teardown to trigger a use-after-free.

Linux kernel
Debian Linux
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux (Debian package)

Install security update from vendor's repository.

linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
linux (Debian package) - update to 6.12.111-1

• https://git.kernel.org/stable/c/0e753899627b5e28a9fea8bca98262a6f65a2452
• https://git.kernel.org/stable/c/8cc98db4fc590e6c7d9db6529320982ee16c5d1d
• https://git.kernel.org/stable/c/c8279ae8df68cce9cd3b785e85f7a86c80a46e78

• Use-after-free in Linux kernel smb server
• Debian update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more