Use-after-free in Linux kernel - CVE-2026-64061

Vulnerability identifier: #VU138579

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-2026-64061

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in netfs_read_gaps() when processing buffered reads with a sink folio. A local user can trigger the flaw to cause a denial of service.

The issue was detected by KASAN as a write-after-free during kernel handling of data received over a TCP socket.

Linux kernel
Ubuntu
linux-ibm (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

• https://git.kernel.org/stable/c/2a39d49c8d97df8cb8fa80c10859bc1ba7358c6b
• https://git.kernel.org/stable/c/3e5dd91b87a8b1450217b56a336bee315f40da7d
• https://git.kernel.org/stable/c/412e8bad48967fd34295866636c028befd27d8b9
• https://git.kernel.org/stable/c/d4f4bc87c76511cf2532448b0fa40c25e894bd7d

• Use-after-free in Linux kernel netfs
• Ubuntu update for linux-ibm
• Ubuntu update for linux-azure
• Ubuntu update for linux-aws
• Ubuntu update for linux-nvidia-bos
• Ubuntu update for linux-nvidia