4.7

CVE-2021-27854: ieee 802.2 Authentication Bypass by Spoofing

CVSS: 4.7v3.1MediumModified
Published 27-09-2022Last modified 04-11-2025
Open JSON

Vulnerability summary

CVE-2021-27854 is a medium (CVSS 4.7) Authentication Bypass by Spoofing vulnerability in ieee 802.2. EPSS estimates a 0.71% chance of exploitation in the next 30 days, higher than 52.7% of scored vulnerabilities.

Overall risk
19/100
0100
Low · default modelHow is this calculated?
CVSS score
4.7/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.71%
0%100%
Low · +0.02 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 27-09-2022
    PublishedVulnerability first disclosed.
  2. 04-11-2025
    Last modifiedVulnerability information updated.

Description

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 metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.71%

Chance of exploitation in the next 30 days

Percentile

53%

Versus all other CVEs

30-day change

+0.02 pp

From 0.69% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.71%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ieee2 products
Ietf2 products

2 vendors · 4 products

References

6 links