NULL pointer dereference in Linux kernel - CVE-2021-47223
Published: May 31, 2024 / Updated: May 14, 2025
Vulnerability identifier: #VU90464
CSH Severity: Low
CVSSv4.0: 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/E:U/U:Clear
CVE-ID: CVE-2021-47223
CWE-ID: CWE-476
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerable software:
Linux kernel
Linux kernel
Software vendor:
Linux Foundation
Linux Foundation
Description
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.
Remediation
Install update from vendor's website.
External links
- 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