CVE-2021-27861

CVSS V2 None CVSS V3 Medium 4.7

Description

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

Overview

CVE ID
CVE-2021-27861

Assigner
cret@cert.org

Vulnerability Status
Modified

Published Version
2022-09-27T19:15:09

Last Modified Date
2022-10-12T13:15:10

Weakness Enumerations

CWE	URL
CWE-290	http://cwe.mitre.org/data/definitions/290.html

CPE Configuration (Product)

CPE	Vulnerable	Operator	Version Start	Version End
cpe:2.3:a:ieee:ieee_802.2::::::::	1	OR		802.2h-1997
cpe:2.3:a:ietf:p802.1q::::::::	1	OR		d1.0

CVSS Version 3

Version
3.1

Vector String
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Attack Vector
ADJACENT_NETWORK

Attack Compatibility
LOW

Privileges Required
NONE

User Interaction
NONE

Scope
CHANGED

Confidentiality Impact
NONE

Availability Impact
NONE

Base Score
4.7

Base Severity
MEDIUM

Exploitability Score
2.8

Impact Score
1.4

References

Reference URL	Reference Tags
https://blog.champtar.fr/VLAN0_LLC_SNAP/
https://datatracker.ietf.org/doc/draft-ietf-v6ops-ra-guard/08/	Third Party Advisory
https://kb.cert.org/vuls/id/855201
https://standards.ieee.org/ieee/802.1Q/10323/	Third Party Advisory
https://standards.ieee.org/ieee/802.2/1048/	Third Party Advisory

Sources

Source Name	Source URL
NIST	https://nvd.nist.gov/vuln/detail/CVE-2021-27861
MITRE	https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-27861

History

Created	Old Value	New Value	Data Type	Notes
2022-09-27 20:00:10				Added to TrackCVE
2022-12-07 04:59:34	cert@cert.org	cret@cert.org	CVE Assigner	updated
2022-12-07 04:59:34	2022-09-27T19:15Z	2022-09-27T19:15:09	CVE Published Date	updated
2022-12-07 04:59:34		2022-10-12T13:15:10	CVE Modified Date	updated
2022-12-07 04:59:34		Modified	Vulnerability Status	updated
2022-12-07 04:59:39			References	updated