Vulnerability · Published Sep 27, 2022 · Assigned by certcc
CVE-2021-27862L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with an invalid length during Ethernet to Wifi frame translation
Medium 4.7
In plain English
A medium-severity authentication bypass by spoofing in 802.2 from IEEE. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities).
Severity (CVSS 3.1)4.7Medium
Exploit odds (30 days)0.7%top 47.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers).
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| IEEE | 802.2 | 802.2h-1997 – through 802.2h-1997 |
| IETF | draft-ietf-v6ops-ra-guard-08 | 08 – through 08 |
Weakness: CWE-130, CWE-290 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N