MEDIUM
CVE-2021-27862
CWE-130Published: September 27, 2022· Updated: Jun 17, 2026
4.7
CVSS v3.1
Official Description
Layer 2 network filtering capabilities such as IPv6 RA guard can be bypassed using LLC/SNAP headers with invalid length and Ethernet to Wifi frame conversion (and optionally VLAN0 headers).
Technical Analysis
CVE-2021-27862 requires adjacent network access, limiting remote exploitation but still posing risk in shared or local network environments.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorAdjacent
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeChanged
Impact
ConfidentialityNone
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Affected Vendors & Products
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (9)
→
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https://standards.ieee.org/ieee/802.2/1048/Vendor Advisory
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https://standards.ieee.org/ieee/802.2/1048/Vendor Advisory
Quick Facts
CVE IDCVE-2021-27862
CVSS Score4.7 / 10
SeverityMEDIUM
WeaknessCWE-130
CISA KEVNo
Affected2 vendor(s)
PublishedSep 27, 2022
Related CVEs (CWE-130)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-27862 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.