NULL pointer dereference in Linux kernel - CVE-2021-47223
Published: May 31, 2024 / Updated: May 14, 2025
Vulnerability details
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to NULL pointer dereference within the br_vlan_tunnel_lookup(), __vlan_tunnel_info_add(), br_handle_ingress_vlan_tunnel() and br_handle_egress_vlan_tunnel() functions in net/bridge/br_vlan_tunnel.c. A local user can perform a denial of service (DoS) attack.
Affected software
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
How to mitigate CVE-2021-47223
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
External References
- https://git.kernel.org/stable/c/ad7feefe7164892db424c45687472db803d87f79
- https://git.kernel.org/stable/c/24a6e55f17aa123bc1fc54b7d3c410b41bc16530
- https://git.kernel.org/stable/c/a2241e62f6b4a774d8a92048fdf59c45f6c2fe5c
- https://git.kernel.org/stable/c/fe0448a3fad365a747283a00a1d1ad5e8d6675b7
- https://git.kernel.org/stable/c/abb02e05cb1c0a30dd873a29f33bc092067dc35d
- https://git.kernel.org/stable/c/58e2071742e38f29f051b709a5cca014ba51166f
- 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