Out-of-bounds read in Linux kernel - CVE-2026-63963

Vulnerability identifier: #VU138683

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-63963

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to an out-of-bounds read in Discover Identity ACK handlers in the tcpm subsystem when processing a device-supplied VDO count. A remote attacker can provide a crafted count value to disclose sensitive information.

Linux kernel
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Live Patching
SUSE Real Time Module
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
Ubuntu
kgraft-patch-4_12_14-122_333-default
kernel-livepatch-SLE15-SP7-RT_Update_21-debugsource
kernel-livepatch-6_4_0-150700_7_78-rt
kernel-livepatch-6_4_0-150700_7_78-rt-debuginfo
kernel-livepatch-6_4_0-150700_53_84-default
kernel-livepatch-6_4_0-150700_53_84-default-debuginfo
kernel-livepatch-SLE15-SP7_Update_22-debugsource
ocfs2-kmp-default-debuginfo
kernel-default-devel
gfs2-kmp-default-debuginfo
gfs2-kmp-default
kernel-default-devel-debuginfo
kernel-macros
kernel-source
kernel-devel
kernel-default-man
cluster-md-kmp-default-debuginfo
kernel-default-base
kernel-syms
kernel-default-base-debuginfo
cluster-md-kmp-default
ocfs2-kmp-default
dlm-kmp-default-debuginfo
dlm-kmp-default
kernel-default-debuginfo
kernel-default-kgraft-devel
kernel-default-debugsource
kernel-default-kgraft
kernel-default
kernel-rt
cluster-md-kmp-rt-debuginfo
kernel-devel-rt
kernel-source-rt
ocfs2-kmp-rt
gfs2-kmp-rt-debuginfo
gfs2-kmp-rt
dlm-kmp-rt-debuginfo
cluster-md-kmp-rt
kernel-rt-debugsource
kernel-syms-rt
dlm-kmp-rt
kernel-rt-devel
kernel-rt-devel-debuginfo
kernel-rt-debuginfo
ocfs2-kmp-rt-debuginfo
kernel-default-extra-debuginfo
kernel-default-extra
kernel-azure
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump
kernel-azure-debugsource
kernel-64kb
kernel-azure-devel
kernel-default-livepatch
kernel-default-livepatch-devel
reiserfs-kmp-default-debuginfo
reiserfs-kmp-default
kernel-obs-build-debugsource
kernel-obs-build
kernel-docs
kernel-64kb-devel
kernel-64kb-debugsource
kernel-64kb-devel-debuginfo
kernel-64kb-debuginfo
kernel-zfcpdump-debuginfo
linux-ibm (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-azure-7.0 (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
kgraft-patch-4_12_14-122_333-default - update to 1-8.3.3
kernel-livepatch-SLE15-SP7-RT_Update_21-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_78-rt - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_78-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_84-default - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_84-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-SLE15-SP7_Update_22-debugsource - update to 1-150700.15.3.1
ocfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-devel - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
gfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
gfs2-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-devel-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-macros - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-source - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-devel - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-man - update to 4.12.14-122.333.2
cluster-md-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-base - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1.150700.17.47.1
kernel-syms - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-base-debuginfo - update to 4.12.14-122.333.2
cluster-md-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
ocfs2-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
dlm-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
dlm-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-kgraft-devel - update to 4.12.14-122.333.2
kernel-default-debugsource - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-kgraft - update to 4.12.14-122.333.2
kernel-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-rt - update to 6.4.0-150700.7.78.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
kernel-devel-rt - update to 6.4.0-150700.7.78.1
kernel-source-rt - update to 6.4.0-150700.7.78.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.78.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
gfs2-kmp-rt - update to 6.4.0-150700.7.78.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.78.1
kernel-rt-debugsource - update to 6.4.0-150700.7.78.1
kernel-syms-rt - update to 6.4.0-150700.7.78.1
dlm-kmp-rt - update to 6.4.0-150700.7.78.1
kernel-rt-devel - update to 6.4.0-150700.7.78.1
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.78.1
kernel-rt-debuginfo - update to 6.4.0-150700.7.78.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.84.1
kernel-default-extra - update to 6.4.0-150700.53.84.1
kernel-azure - update to 6.4.0-150700.53.84.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.84.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.84.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.84.1
kernel-zfcpdump - update to 6.4.0-150700.53.84.1
kernel-azure-debugsource - update to 6.4.0-150700.53.84.1
kernel-64kb - update to 6.4.0-150700.53.84.1
kernel-azure-devel - update to 6.4.0-150700.53.84.1
kernel-default-livepatch - update to 6.4.0-150700.53.84.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.84.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.84.1
reiserfs-kmp-default - update to 6.4.0-150700.53.84.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.84.1
kernel-obs-build - update to 6.4.0-150700.53.84.1
kernel-docs - update to 6.4.0-150700.53.84.1
kernel-64kb-devel - update to 6.4.0-150700.53.84.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.84.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.84.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.84.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.84.1
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-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1016.16
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

• https://git.kernel.org/stable/c/569f7971542eb10025d8a0989b83f28a29d8ba20
• https://git.kernel.org/stable/c/8fbc349e8383125dd2d8de1c1e926279d398ab17
• https://git.kernel.org/stable/c/ed8649f3822e211d025bcab5158af6f8a38c8705
• https://git.kernel.org/stable/c/f9d787fbe83127105e42088cca40e5118db0d810

• Out-of-bounds read in Linux kernel typec tcpm driver
• 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
• Ubuntu update for linux-gcp-7.0
• Ubuntu update for linux-oracle-7.0
• Ubuntu update for linux-azure-7.0
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel