CVE-2021-27853 Information

Description

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.

Reference

https://standards.ieee.org/ieee/802.2/1048/ https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/ https://standards.ieee.org/ieee/802.1Q/10323/ https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-VU855201-J3z8CKTX