CVE-2021-27861CWE-130CWE-290

L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with invalid lengths

Medium · published September 27, 2022

CVSS v3.1
4.7
EPSS
1%
Percentile
51.1
In the wild
Unconfirmed
What it is

Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length (and optionally VLAN0 headers)

The record
Technical detail
CVSS v3.1
4.7 · MEDIUM
Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00663 · 51.1th percentile
Weaknesses
CWE-130 · Improper Handling of Length Parameter Inconsistency; CWE-290 · Authentication Bypass by Spoofing
Published
2022-09-27T18:40Z
EPSS history
Timeline
  • 27 SEP 18:40Z
    L2 network filtering bypass using stacked VLAN0 and LLC/SNAP headers with invalid lengths
    cvelistv5