CVE-2005-4440 json
The 802.1q VLAN protocol allows remote attackers to bypass network segmentation and spoof VLAN traffic via a message with two 802.1q tags,…
published 2005-12-21 20 y ago modified 2026-06-16 4 mo ago also EUVD-2005-4435
- cvss
- 5.0
- version 2.0, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.6%
- EPSS 1.6% chance of exploitation in 30 days, percentile 76%
- public exploits
- 0
- none known
Summary
The 802.1q VLAN protocol allows remote attackers to bypass network segmentation and spoof VLAN traffic via a message with two 802.1q tags, which causes the second tag to be redirected from a downstream switch after the first tag has been stripped, as demonstrated by Yersinia, aka "double-tagging VLAN jumping attack."
Exploit prediction
1.61% chance of exploitation in the next 30 days, higher than 76% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:P/A:N |
References
Sources
- CVE List CVE-2005-4440
- NVD CVE-2005-4440
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