CVE-2021-27862

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).

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
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/802.2/1048/	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/802.2/1048/	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:ieee:ieee_802.2:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:a:ietf:p802.1q:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2022-09-27 19:15

Updated : 2025-05-21 15:15

NVD link : CVE-2021-27862

Mitre link : CVE-2021-27862

CVE.ORG link : CVE-2021-27862

JSON object : View

Products Affected

ieee

ieee_802.2

ietf

p802.1q

CWE

CWE-130

Improper Handling of Length Parameter Inconsistency

CWE-290

Authentication Bypass by Spoofing

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