CVE-2006-4775
HIGH · CVSS 7.8EPSS 5.1%EU EUVD
The VLAN Trunking Protocol (VTP) feature in Cisco IOS 12.1(19) and CatOS allows remote attackers to cause a denial of service by sending a VTP update with a revision value of 0x7FFFFFFF, which is incremented to 0x80000000 and is interpreted as a negative number in a signed context.
Key facts
- CVSS score
- 7.8 (v2.0)
- Severity
- HIGH
- CVSS vector
AV:N/AC:L/Au:N/C:N/I:N/A:C- Weakness (CWE)
- CWE-399
- EPSS score
- 5.1% (92th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2006-4762)
- Published
- September 14, 2006
- NVD last modified
- June 16, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2006-4762 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.
View on the EU Vulnerability DatabaseAffected products
- cisco / catos
- cisco / ios
References
- http://secunia.com/advisories/21896(Vendor Advisory)
- http://secunia.com/advisories/21902(Vendor Advisory)
- http://securitytracker.com/id?1016843
- http://www.cisco.com/warp/public/707/cisco-sr-20060913-vtp.shtml(Patch)
- http://www.kb.cert.org/vuls/id/175148(US Government Resource)
- http://www.osvdb.org/28776
- http://www.phenoelit.de/stuff/CiscoVTP.txt
- http://www.securityfocus.com/archive/1/445896/100/0/threaded
- http://www.securityfocus.com/archive/1/445938/100/0/threaded
- http://www.securityfocus.com/bid/19998
- http://www.vupen.com/english/advisories/2006/3600(Vendor Advisory)
- https://exchange.xforce.ibmcloud.com/vulnerabilities/28925
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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