vulnerability
Cisco IOS: CVE-2021-27861: Vulnerabilities in Layer 2 Network Security Controls Affecting Cisco Products: September 2022
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 3 | (AV:A/AC:L/Au:N/C:N/I:P/A:N) | Sep 27, 2022 | Jan 21, 2026 | Jan 21, 2026 |
Severity
3
CVSS
(AV:A/AC:L/Au:N/C:N/I:P/A:N)
Published
Sep 27, 2022
Added
Jan 21, 2026
Modified
Jan 21, 2026
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)
Solution
cisco-ios-upgrade-latest
NEW
Explore Exposure Command
Confidently identify and prioritize exposures from endpoint to cloud with full attack surface visibility and threat-aware risk context.