Integer underflow in Linux kernel - CVE-2026-68123

Vulnerability identifier: #VU142201

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-2026-68123

CWE-ID: CWE-191

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 an integer underflow in queue_userspace_packet() in the openvswitch subsystem when processing userspace actions on segmented gso packets after truncation. A local user can send a specially crafted packet that triggers truncation and segmentation handling to cause a denial of service.

The issue occurs because truncation state is reused across smaller gso segments, allowing the preserved length value to exceed the current packet length.

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
kernel-livepatch-SLE15-SP7_Update_21-debugsource
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo
kernel-livepatch-6_4_0-150700_53_81-default
kernel-default-livepatch
kernel-64kb-devel-debuginfo
kernel-64kb-debugsource
kernel-docs
kernel-syms
kernel-obs-build
kernel-obs-build-debugsource
kernel-source
reiserfs-kmp-default
reiserfs-kmp-default-debuginfo
kernel-64kb-devel
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
kernel-64kb-debuginfo
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
cluster-md-kmp-default-debuginfo
kernel-default-debugsource
kernel-default
kernel-default-devel-debuginfo
kernel-default-devel
kernel-macros
kernel-devel
kernel-zfcpdump
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
kernel-64kb
gfs2-kmp-default
kernel-default-base

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-livepatch-SLE15-SP7_Update_21-debugsource - 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-6_4_0-150700_53_81-default - update to 1-150700.15.3.1
kernel-default-livepatch - update to 6.4.0-150700.53.81.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.81.1
kernel-docs - 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-obs-build-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-64kb-devel - 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
kernel-64kb-debuginfo - 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
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-debugsource - update to 6.4.0-150700.53.81.1
kernel-default - update to 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-devel - update to 6.4.0-150700.53.81.1
kernel-macros - update to 6.4.0-150700.53.81.1
kernel-devel - update to 6.4.0-150700.53.81.1
kernel-zfcpdump - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb - update to 6.4.0-150700.53.81.1
gfs2-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

• https://git.kernel.org/stable/c/100a23b1613e9218e0af654ef102352c713f0263
• https://git.kernel.org/stable/c/4032f8ed10fcb84d41c508dfb04be96589f78dfe
• https://git.kernel.org/stable/c/a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855
• https://git.kernel.org/stable/c/ea85dbcbe8d4056ecb54352f97743d138ea4c407
• https://git.kernel.org/stable/c/fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc

• Integer underflow in Linux kernel openvswitch
• SUSE update for the Linux Kernel