Out-of-bounds read in Linux kernel - CVE-2026-80603

Vulnerability identifier: #VU146273

CSH Severity: Medium

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

CVE-ID: CVE-2026-80603

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause incorrect connection tracking state.

The vulnerability exists due to an out-of-bounds read in the parse_dcc() function in nf_conntrack_irc when parsing DCC command data without a newline present. A remote attacker can send specially crafted IRC DCC command data to cause incorrect connection tracking state.

The stray read may consume an uninitialized or stale byte, which can lead to an incorrect DCC IP address or port being recorded in the conntrack expectation.

Linux kernel
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Live Patching
kgraft-patch-4_12_14-122_328-default
dlm-kmp-default
kernel-default-man
kernel-macros
kernel-devel
kernel-source
kernel-default-devel-debuginfo
kernel-default-base
kernel-default-devel
cluster-md-kmp-default
gfs2-kmp-default
ocfs2-kmp-default-debuginfo
gfs2-kmp-default-debuginfo
kernel-default
ocfs2-kmp-default
kernel-default-base-debuginfo
dlm-kmp-default-debuginfo
cluster-md-kmp-default-debuginfo
kernel-syms
kernel-default-kgraft
kernel-default-debuginfo
kernel-default-kgraft-devel
kernel-default-debugsource

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kgraft-patch-4_12_14-122_328-default - update to 1-8.5.1
dlm-kmp-default - update to 4.12.14-122.328.1
kernel-default-man - update to 4.12.14-122.328.1
kernel-macros - update to 4.12.14-122.328.1
kernel-devel - update to 4.12.14-122.328.1
kernel-source - update to 4.12.14-122.328.1
kernel-default-devel-debuginfo - update to 4.12.14-122.328.1
kernel-default-base - update to 4.12.14-122.328.1
kernel-default-devel - update to 4.12.14-122.328.1
cluster-md-kmp-default - update to 4.12.14-122.328.1
gfs2-kmp-default - update to 4.12.14-122.328.1
ocfs2-kmp-default-debuginfo - update to 4.12.14-122.328.1
gfs2-kmp-default-debuginfo - update to 4.12.14-122.328.1
kernel-default - update to 4.12.14-122.328.1
ocfs2-kmp-default - update to 4.12.14-122.328.1
kernel-default-base-debuginfo - update to 4.12.14-122.328.1
dlm-kmp-default-debuginfo - update to 4.12.14-122.328.1
cluster-md-kmp-default-debuginfo - update to 4.12.14-122.328.1
kernel-syms - update to 4.12.14-122.328.1
kernel-default-kgraft - update to 4.12.14-122.328.1
kernel-default-debuginfo - update to 4.12.14-122.328.1
kernel-default-kgraft-devel - update to 4.12.14-122.328.1
kernel-default-debugsource - update to 4.12.14-122.328.1

• https://git.kernel.org/stable/c/2393f0bd7a467ad475598f3a5b9de27ca36e3037
• https://git.kernel.org/stable/c/2b70f61f569bb29acb380e6f616a1bbdee15668f
• https://git.kernel.org/stable/c/437e0a3854b3a44ec15afa9ab88ec215adf3a2fd
• https://git.kernel.org/stable/c/910c33e4a8c046c3cc1fa5a465a4d41a1bb398f1
• https://git.kernel.org/stable/c/abb8c32b88ea3f46beb68c34fe9a3ac8ed664e7e
• https://git.kernel.org/stable/c/aff589556ed772cb1c0c2d7b4d91ec45c0c39416
• https://git.kernel.org/stable/c/eeef3b81f449560653662df2dde6f6fe247c5365
• https://git.kernel.org/stable/c/ef6400ca25a13fd6dedbe8ef4a1d0979bbbfe88a

• Out-of-bounds read in Linux kernel netfilter
• SUSE update for the Linux Kernel