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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| IEEE | 802.2 | 802.2h-1997 – ≤ 802.2h-1997 | — |
| IETF | draft-ietf-v6ops-ra-guard | 08 – ≤ 08 | — |
| IETF | P802.1Q | D1.0 – ≤ D1.0 | — |
Advisories 1
- WID-SEC-2022-1551 Layer 2 Netzwerksicherheitskontrollen: Mehrere Schwachstellen ermöglichen Umgehen von Sicherheitsvorkehrungen BSI CERT-Bund (WID) · Oct 4, 2023
References
- https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/
- https://standards.ieee.org/ieee/802.2/1048/
- https://standards.ieee.org/ieee/802.1Q/10323/
- 20220927 Vulnerabilities in Layer 2 Network Security Controls Affecting Cisco Products: September 2022 vendor-advisory
- https://kb.cert.org/vuls/id/855201
- https://blog.champtar.fr/VLAN0_LLC_SNAP/