Division by zero in Linux kernel - CVE-2026-80847

Vulnerability identifier: #VU147070

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-2026-80847

CWE-ID: CWE-369

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 divide-by-zero error in tcp_select_initial_window() when processing route-derived advertised MSS values. A local user can configure a route with a too-small RTAX_ADVMSS value to cause a denial of service.

The default advertised MSS path is also affected when the effective advertised MSS is reduced by the route MTU and min_adv_mss.

Linux kernel
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
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
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Live Patching
SUSE Real Time Module
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
kgraft-patch-4_12_14-122_333-default
kernel-livepatch-6_4_0-150700_7_78-rt-debuginfo
kernel-livepatch-6_4_0-150700_7_78-rt
kernel-livepatch-SLE15-SP7-RT_Update_21-debugsource
kernel-livepatch-6_4_0-150700_53_84-default-debuginfo
kernel-livepatch-SLE15-SP7_Update_22-debugsource
kernel-livepatch-6_4_0-150700_53_84-default
kernel-default-base
gfs2-kmp-default
gfs2-kmp-default-debuginfo
kernel-default-devel
ocfs2-kmp-default-debuginfo
cluster-md-kmp-default-debuginfo
kernel-default
kernel-default-kgraft
kernel-default-debugsource
dlm-kmp-default
kernel-syms
kernel-default-base-debuginfo
cluster-md-kmp-default
kernel-macros
kernel-default-kgraft-devel
kernel-default-debuginfo
ocfs2-kmp-default
dlm-kmp-default-debuginfo
kernel-source
kernel-devel
kernel-default-man
kernel-default-devel-debuginfo
dlm-kmp-rt
kernel-rt
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
kernel-rt-devel
kernel-rt-devel-debuginfo
kernel-rt-debuginfo
cluster-md-kmp-rt-debuginfo
ocfs2-kmp-rt-debuginfo
kernel-default-extra-debuginfo
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump
kernel-64kb
kernel-default-extra
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-devel
kernel-azure-debugsource
kernel-azure
kernel-default-livepatch
kernel-default-livepatch-devel
reiserfs-kmp-default-debuginfo
reiserfs-kmp-default
kernel-64kb-debuginfo
kernel-obs-build-debugsource
kernel-obs-build
kernel-docs
kernel-64kb-devel
kernel-64kb-debugsource
kernel-64kb-devel-debuginfo
linux (Debian package)

Install security update from vendor's repository.

kgraft-patch-4_12_14-122_333-default - update to 1-8.3.3
kernel-livepatch-6_4_0-150700_7_78-rt-debuginfo - 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-SLE15-SP7-RT_Update_21-debugsource - update to 1-150700.1.3.1
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
kernel-livepatch-6_4_0-150700_53_84-default - update to 1-150700.15.3.1
kernel-default-base - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1.150700.17.47.1
gfs2-kmp-default - 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
kernel-default-devel - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
ocfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
cluster-md-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default - 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-debugsource - 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-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
kernel-macros - 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-debuginfo - 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
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
kernel-default-devel-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
dlm-kmp-rt - update to 6.4.0-150700.7.78.1
kernel-rt - 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
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
cluster-md-kmp-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-zfcpdump-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-64kb - update to 6.4.0-150700.53.84.1
kernel-default-extra - 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-azure-devel - update to 6.4.0-150700.53.84.1
kernel-azure-debugsource - update to 6.4.0-150700.53.84.1
kernel-azure - 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-64kb-debuginfo - 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
linux (Debian package) - update to 6.12.111-1

• https://git.kernel.org/stable/c/31cf2349361902769dc323e4dbf4b449795ec288
• https://git.kernel.org/stable/c/6b8c20bf61924dfc38fefb145c9f7406d73fae53
• https://git.kernel.org/stable/c/870a9e42ecc6fe1b8c25d87af043cb0d9c178fe1

• Division by zero in Linux kernel ipv6
• Debian update for linux
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel