CVE-2009-0635
HIGH · CVSS 7.1EPSS 2.5%EU EUVD
Memory leak in the Cisco Tunneling Control Protocol (cTCP) encapsulation feature in Cisco IOS 12.4, when an Easy VPN (aka EZVPN) server is enabled, allows remote attackers to cause a denial of service (memory consumption and device crash) via a sequence of TCP packets.
Key facts
- CVSS score
- 7.1 (v2.0)
- Severity
- HIGH
- CVSS vector
AV:N/AC:M/Au:N/C:N/I:N/A:C- Weakness (CWE)
- CWE-399
- EPSS score
- 2.5% (85th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2009-0638)
- Published
- March 27, 2009
- NVD last modified
- June 16, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2009-0638 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.
View on the EU Vulnerability DatabaseAffected products
- cisco / ios
- cisco / ios
- cisco / ios
References
- http://secunia.com/advisories/34438(Vendor Advisory)
- http://www.cisco.com/en/US/products/products_security_advisory09186a0080a90459.shtml(Patch, Vendor Advisory)
- http://www.cisco.com/en/US/products/products_security_advisory09186a0080a90469.shtml(Patch, Vendor Advisory)
- http://www.securityfocus.com/bid/34246
- http://www.securitytracker.com/id?1021895
- http://www.vupen.com/english/advisories/2009/0851(Vendor Advisory)
- https://exchange.xforce.ibmcloud.com/vulnerabilities/49417
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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