PT-2022-9876 · Ieee+1 · 802.2+3

Published 2022-09-27 · Updated 2022-10-12 · CVE-2021-27854

Positive Technologies (AI Summary)

CVSS v3.1

4.7

Medium

Base vector

AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Name of the Vulnerable Software and Affected Versions No specific software or versions are mentioned.

Description The issue allows Layer 2 network filtering capabilities, such as IPv6 RA guard, to be bypassed. This can be achieved by using specific combinations of VLAN 0 headers, LLC/SNAP headers, and converting frames from Ethernet to Wifi and its reverse.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Authentication Bypass by Spoofing

Weakness Enumeration

CWE-290

Related Identifiers

CVE-2021-27854

Affected Products

802.2

P802.1Q

Draft-Ietf-V6Ops-Ra-Guard

Ieee 802.2

References · 9

• https://osv.dev/vulnerability/CVE-2021-27854 · Vendor Advisory
• https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08 · Vendor Advisory
• https://standards.ieee.org/ieee/802.2/1048 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-27854 · Security Note
• https://standards.ieee.org/ieee/802.1Q/10323 · Vendor Advisory
• https://kb.cert.org/vuls/id/855201 · Note
• https://blog.champtar.fr/VLAN0_LLC_SNAP · Note
• https://t.me/cibsecurity/50531 · Telegram Post
• https://t.me/true_secator/3491 · Telegram Post