Use-after-free in Linux kernel - CVE-2026-64534

Vulnerability identifier: #VU139847

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-64534

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to use-after-free in nvmet_tcp_try_recv_ddgst() when processing a command with a data digest mismatch after request initialization previously failed. A remote attacker can send a specially crafted request to cause a denial of service.

The issue can lead to a refcount underflow, kernel warnings, and a permanent workqueue deadlock.

Linux kernel
Debian Linux
openEuler
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-headers
kernel-source
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python3-perf
python3-perf-debuginfo
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel - update to 5.10.0-328.0.0.229
bpftool - update to 5.10.0-328.0.0.229
bpftool-debuginfo - update to 5.10.0-328.0.0.229
kernel-debuginfo - update to 5.10.0-328.0.0.229
kernel-debugsource - update to 5.10.0-328.0.0.229
kernel-devel - update to 5.10.0-328.0.0.229
kernel-headers - update to 5.10.0-328.0.0.229
kernel-source - update to 5.10.0-328.0.0.229
kernel-tools - update to 5.10.0-328.0.0.229
kernel-tools-debuginfo - update to 5.10.0-328.0.0.229
kernel-tools-devel - update to 5.10.0-328.0.0.229
perf - update to 5.10.0-328.0.0.229
perf-debuginfo - update to 5.10.0-328.0.0.229
python3-perf - update to 5.10.0-328.0.0.229
python3-perf-debuginfo - update to 5.10.0-328.0.0.229
linux (Debian package) - update to 6.12.100-1

• https://git.kernel.org/stable/c/22ec7a9fe9153d2737ee9b2fa6d2e43a1491decf
• https://git.kernel.org/stable/c/2ed3c9d955e8cd6361f130623baa664a75fb345f
• https://git.kernel.org/stable/c/4606467a75cfc16721937272ed29462a750b60c8
• https://git.kernel.org/stable/c/ba35b1c674ca3841c0dfadd698f2c1b3ec542d4e
• https://git.kernel.org/stable/c/c7874dad84b20433c0fe3919f291a762d40de08b
• https://git.kernel.org/stable/c/d306da8833e75f669d93424fd84940236f3850bc
• https://git.kernel.org/stable/c/e602c93b25bda4a9d0ff1791a4bdbfdcbb074af1

• Use-after-free in Linux kernel nvme target driver
• Debian update for linux
• openEuler 22.03 LTS SP4 update for kernel