CVE-2009-0635 json
Memory leak in the Cisco Tunneling Control Protocol (cTCP) encapsulation feature in Cisco IOS 12.4, when an Easy VPN (aka EZVPN) server is…
published 2009-03-27 17 y ago modified 2026-06-16 4 mo ago also EUVD-2009-0638
- cvss
- 7.1
- version 2.0, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.5%
- EPSS 2.5% chance of exploitation in 30 days, percentile 84%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
Exploit prediction
2.51% chance of exploitation in the next 30 days, higher than 84% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 2.0 | 7.1 | AV:N/AC:M/Au:N/C:N/I:N/A:C |
Classification
- Weakness
-
- CWE-399 Resource Management Errors
- Technology feeds
References
-
cisco.com
/en/US/products/products_security_advisory09186a0080a90459.shtml
vendor-advisory, patch
-
cisco.com
/en/US/products/products_security_advisory09186a0080a90469.shtml
patch, vendor-advisory
-
secunia.com
/advisories/34438
third-party-advisory, vendor-advisory
-
vupen.com
/english/advisories/2009/0851
vdb-entry, vendor-advisory
-
securityfocus.com
/bid/34246
vdb-entry
-
exchange.xforce.ibmcloud.com
/vulnerabilities/49417
vdb-entry
-
securitytracker.com
/id?1021895
vdb-entry
Sources
- CVE List CVE-2009-0635
- NVD CVE-2009-0635
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