CVE-2021-27854

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.

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/802.1Q/10323/	Vendor Advisory
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 : 2024-02-28 19:29

NVD link : CVE-2021-27854

Mitre link : CVE-2021-27854

CVE.ORG link : CVE-2021-27854

JSON object : View

Products Affected

ietf

p802.1q

ieee

ieee_802.2

CWE

CWE-290

Authentication Bypass by Spoofing

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