CVE-2021-27854
4.7MEDIUMLayer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using combinations of VLAN 0 headers, LLC/SNAP headers, and converting frames from Ethernet to Wifi and its reverse.
Published: 9/27/2022Updated: 11/4/2025
Description
Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using combinations of VLAN 0 headers, LLC/SNAP headers, and converting frames from Ethernet to Wifi and its reverse.
AI AnalysisPowered by AI
Affected Products
ieeeieee_802.2
ietfp802.1q
References
- https://blog.champtar.fr/VLAN0_LLC_SNAP/
- https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/Vendor Advisory
- https://kb.cert.org/vuls/id/855201
- https://standards.ieee.org/ieee/802.1Q/10323/Vendor Advisory
- https://standards.ieee.org/ieee/802.2/1048/Vendor Advisory
- https://blog.champtar.fr/VLAN0_LLC_SNAP/
- https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/Vendor Advisory
- https://kb.cert.org/vuls/id/855201
- https://standards.ieee.org/ieee/802.1Q/10323/Vendor Advisory
- https://standards.ieee.org/ieee/802.2/1048/Vendor Advisory
- https://www.kb.cert.org/vuls/id/855201