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Vulnerability record · CVE-2006-3906 · published 27 July 2006

CVE-2006-3906: Cisco ios vulnerability

Cisco · Ios

Internet Key Exchange (IKE) version 1 protocol, as implemented on Cisco IOS, VPN 3000 Concentrators, and PIX firewalls, allows remote attackers to cause a denial of service (resource exhaustion) via a flood of IKE Phase-1 packets that exceed the session expiration rate. NOTE: it has been argued that this is due to a design weakness of the IKE version 1 protocol, in which case other vendors and implementations would also be affected.

5.0 CVSS 2.0 Medium EPSS 6.9% · top 6.2%
5.0CVSS 2.0 base score
6.9%EPSS exploitation probability, 30 days
NoNot in CISA KEV
21Affected product versions listed by NVD
20References
16 Jun 2026Last modified by NVD

Description

Internet Key Exchange (IKE) version 1 protocol, as implemented on Cisco IOS, VPN 3000 Concentrators, and PIX firewalls, allows remote attackers to cause a denial of service (resource exhaustion) via a flood of IKE Phase-1 packets that exceed the session expiration rate. NOTE: it has been argued that this is due to a design weakness of the IKE version 1 protocol, in which case other vendors and implementations would also be affected.

AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

21 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://archives.neohapsis.com/archives/bugtraq/2006-07/0531.html
http://securityreason.com/securityalert/1293
http://securitytracker.com/id?1016582
http://www.cisco.com/en/US/tech/tk583/tk372/tsd_technology_security_response09186a00806f33d4.html
http://www.nta-monitor.com/posts/2006/07/cisco-concentrator-dos.html
http://www.osvdb.org/29068
http://www.securityfocus.com/archive/1/441203/100/0/threaded
http://www.securityfocus.com/bid/19176
https://exchange.xforce.ibmcloud.com/vulnerabilities/27972
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5299
http://archives.neohapsis.com/archives/bugtraq/2006-07/0531.html
http://securityreason.com/securityalert/1293
http://securitytracker.com/id?1016582
http://www.cisco.com/en/US/tech/tk583/tk372/tsd_technology_security_response09186a00806f33d4.html
http://www.nta-monitor.com/posts/2006/07/cisco-concentrator-dos.html
http://www.osvdb.org/29068
http://www.securityfocus.com/archive/1/441203/100/0/threaded
http://www.securityfocus.com/bid/19176
https://exchange.xforce.ibmcloud.com/vulnerabilities/27972
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5299

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2006-3906), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.