CVE-2021-27853

Layer 2 network filtering capabilities such as IPv6 RA guard or ARP inspection can be bypassed using combinations of VLAN 0 headers and LLC/SNAP headers.

Red Hat deems this to be a configuration issue. There is no vulnerability in the Linux kernel itself, there is a lot of ways to misuse the filtering facilities provided by the kernel and do insecure filtering rules, but you also have everything to actually set up secure rules.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.