Double free in Linux kernel - CVE-2026-64386

Vulnerability identifier: #VU139590

CSH Severity: Medium

CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-64386

CWE-ID: CWE-415

Exploitation vector: Remote access

Exploit availability: No public exploit available

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

The vulnerability exists due to a double free in query_info() in the smb client when handling replayable query_info requests. A remote user can trigger a replayable error sequence to cause a denial of service.

Linux kernel
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Workstation Extension 15
Basesystem Module
Development Tools Module
Legacy Module
Public Cloud Module
SUSE Linux Enterprise Live Patching
openEuler
Ubuntu
kernel-livepatch-6_4_0-150700_53_81-default
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo
kernel-livepatch-SLE15-SP7_Update_21-debugsource
kernel-docs
kernel-obs-build-debugsource
kernel-64kb-debugsource
kernel-64kb-devel-debuginfo
kernel-64kb-devel
kernel-64kb-debuginfo
kernel-64kb
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump
kernel-devel
kernel-macros
kernel-default-devel
kernel-default-devel-debuginfo
kernel-default
kernel-syms
kernel-obs-build
kernel-default-debugsource
kernel-source
reiserfs-kmp-default
reiserfs-kmp-default-debuginfo
kernel-default-livepatch
kernel-default-livepatch-devel
kernel-azure
kernel-azure-devel
kernel-azure-debugsource
kernel-azure-debuginfo
kernel-azure-devel-debuginfo
kernel-default-extra-debuginfo
kernel-default-extra
cluster-md-kmp-default-debuginfo
gfs2-kmp-default
cluster-md-kmp-default
kernel-default-debuginfo
ocfs2-kmp-default-debuginfo
dlm-kmp-default-debuginfo
ocfs2-kmp-default
gfs2-kmp-default-debuginfo
dlm-kmp-default
kernel-default-base
perf
kernel
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-headers
kernel-extra-modules
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
perf-debuginfo
python3-perf
python3-perf-debuginfo
linux (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-livepatch-6_4_0-150700_53_81-default - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-SLE15-SP7_Update_21-debugsource - update to 1-150700.15.3.1
kernel-docs - update to 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.81.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.81.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb-devel - update to 6.4.0-150700.53.81.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.81.1
kernel-zfcpdump - update to 6.4.0-150700.53.81.1
kernel-devel - update to 6.4.0-150700.53.81.1
kernel-macros - update to 6.4.0-150700.53.81.1
kernel-default-devel - update to 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default - update to 6.4.0-150700.53.81.1
kernel-syms - update to 6.4.0-150700.53.81.1
kernel-obs-build - update to 6.4.0-150700.53.81.1
kernel-default-debugsource - update to 6.4.0-150700.53.81.1
kernel-source - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-livepatch - update to 6.4.0-150700.53.81.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.81.1
kernel-azure - update to 6.4.0-150700.53.81.1
kernel-azure-devel - update to 6.4.0-150700.53.81.1
kernel-azure-debugsource - update to 6.4.0-150700.53.81.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-extra - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
gfs2-kmp-default - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default - update to 6.4.0-150700.53.81.1
kernel-default-debuginfo - update to 6.4.0-150700.53.81.1
ocfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
ocfs2-kmp-default - update to 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
dlm-kmp-default - update to 6.4.0-150700.53.81.1
kernel-default-base - update to 6.4.0-150700.53.81.1.150700.17.45.1
perf - update to 6.6.0-145.3.29.160
kernel - update to 6.6.0-145.3.29.160
kernel-tools-devel - update to 6.6.0-145.3.29.160
kernel-tools-debuginfo - update to 6.6.0-145.3.29.160
kernel-tools - update to 6.6.0-145.3.29.160
kernel-source - update to 6.6.0-145.3.29.160
kernel-headers - update to 6.6.0-145.3.29.160
kernel-extra-modules - update to 6.6.0-145.3.29.160
kernel-devel - update to 6.6.0-145.3.29.160
kernel-debugsource - update to 6.6.0-145.3.29.160
kernel-debuginfo - update to 6.6.0-145.3.29.160
bpftool-debuginfo - update to 6.6.0-145.3.29.160
bpftool - update to 6.6.0-145.3.29.160
perf-debuginfo - update to 6.6.0-145.3.29.160
python3-perf - update to 6.6.0-145.3.29.160
python3-perf-debuginfo - update to 6.6.0-145.3.29.160
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

• https://git.kernel.org/stable/c/100fb7c455fa86d248b8bd7bb9de757c192870b4
• https://git.kernel.org/stable/c/2a88561d66eb855813cf004a0abe648bbb17de5e
• https://git.kernel.org/stable/c/3c81dda84799f76b42aec598564316e2964440db
• https://git.kernel.org/stable/c/89234773e8348918111aa15f6922b58cf3843364
• https://git.kernel.org/stable/c/f1add4acb656f5a82806a1ab0e63fed3d8b1bfca

• Double free in Linux kernel smb client
• openEuler 24.03 LTS SP3 update for kernel
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-gcp-7.0
• SUSE update for the Linux Kernel