Integer underflow in Linux kernel - CVE-2021-47222

Vulnerability identifier: #VU91666

CSH Severity: Low

CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2021-47222

CWE-ID: CWE-191

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to execute arbitrary code.

The vulnerability exists due to integer underflow within the br_handle_egress_vlan_tunnel() function in net/bridge/br_vlan_tunnel.c. A local user can execute arbitrary code.

Linux kernel
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise High Availability Extension 12
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_247-default
kernel-default-devel
kernel-default-devel-debuginfo
kernel-default-man
kernel-devel
kernel-macros
kernel-source
gfs2-kmp-default
gfs2-kmp-default-debuginfo
kernel-default-base-debuginfo
cluster-md-kmp-default
ocfs2-kmp-default
kernel-syms
kernel-default
kernel-default-base
cluster-md-kmp-default-debuginfo
dlm-kmp-default
dlm-kmp-default-debuginfo
ocfs2-kmp-default-debuginfo
kernel-default-kgraft
kernel-default-kgraft-devel
kernel-default-debuginfo
kernel-default-debugsource

Install update from vendor's website.

Linux kernel - addressed in versions 4.14.238, 4.19.196, 5.4.128, 5.10.46, 5.12.13, 5.13
kgraft-patch-4_12_14-122_247-default - update to 1-8.3.1
kernel-default-devel - update to 4.12.14-122.247.1
kernel-default-devel-debuginfo - update to 4.12.14-122.247.1
kernel-default-man - update to 4.12.14-122.247.1
kernel-devel - update to 4.12.14-122.247.1
kernel-macros - update to 4.12.14-122.247.1
kernel-source - update to 4.12.14-122.247.1
gfs2-kmp-default - update to 4.12.14-122.247.1
gfs2-kmp-default-debuginfo - update to 4.12.14-122.247.1
kernel-default-base-debuginfo - update to 4.12.14-122.247.1
cluster-md-kmp-default - update to 4.12.14-122.247.1
ocfs2-kmp-default - update to 4.12.14-122.247.1
kernel-syms - update to 4.12.14-122.247.1
kernel-default - update to 4.12.14-122.247.1
kernel-default-base - update to 4.12.14-122.247.1
cluster-md-kmp-default-debuginfo - update to 4.12.14-122.247.1
dlm-kmp-default - update to 4.12.14-122.247.1
dlm-kmp-default-debuginfo - update to 4.12.14-122.247.1
ocfs2-kmp-default-debuginfo - update to 4.12.14-122.247.1
kernel-default-kgraft - update to 4.12.14-122.247.1
kernel-default-kgraft-devel - update to 4.12.14-122.247.1
kernel-default-debuginfo - update to 4.12.14-122.247.1
kernel-default-debugsource - update to 4.12.14-122.247.1

• https://git.kernel.org/stable/c/42020f7f37a90d24b9551f5f7eba3f7c7c102968
• https://git.kernel.org/stable/c/84fc1c944e45ab317e2e70a0e7f76fa2a5e43b6e
• https://git.kernel.org/stable/c/79855be6445b6592bddb7bd7167083ec8cdbd73f
• https://git.kernel.org/stable/c/fc7fdd8c5c2ad2fe3e297698be9d4dbe4a4e0579
• https://git.kernel.org/stable/c/25053a8404ba17ca48f5553d487afc1882e9f56c
• https://git.kernel.org/stable/c/cfc579f9d89af4ada58c69b03bcaa4887840f3b3
• https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.238
• https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.196
• https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.46
• https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.13
• https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13
• https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.128

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