TI-2009-00611 Aliases CVE-2009-0635 GHSA-jrx8-5mjp-vjpm

Memory leak in the Cisco Tunneling Control Protocol (cTCP) encapsulation feature in Cisco…

LOW 36CWE-399Published 2009-03-27 · Updated 2024-08-07

Key facts

Attack vector: Network
Privileges required: None
User interaction: — Not recorded in CVSS 2.0
Attack complexity: Medium
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · Complete
Fix status: No fix listed

Attack profile from CVSS 2.0 · NVD. Fix status from CNA. Impact type from CWE-399 and the CVSS impact.

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.

Why it matters now

EPSS 0.02508 84th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPE	Versions	Role	Vendor
cpe:2.3:o:cisco:ios:12.4t:::::::*	12.4t	Vulnerable	Cisco
cpe:2.3:o:cisco:ios:12.4xz:::::::*	12.4xz	Vulnerable	Cisco
cpe:2.3:o:cisco:ios:12.4ya:::::::*	12.4ya	Vulnerable	Cisco

cpe:2.3:o:cisco:ios:12.4t:*:*:*:*:*:*:* Versions 12.4t Vulnerable ·Cisco
cpe:2.3:o:cisco:ios:12.4xz:*:*:*:*:*:*:* Versions 12.4xz Vulnerable ·Cisco
cpe:2.3:o:cisco:ios:12.4ya:*:*:*:*:*:*:* Versions 12.4ya Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2009-0635
2026-10-03 Alias added: GHSA-jrx8-5mjp-vjpm

References

Patch 2

Advisory 1

ADV-2009-0851

TI-2018-00138 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
TI-2017-09019 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
TI-2017-02977 Improper input validation in Cisco IOS and IOS XE Software KEVCVSS 3.1CRITICAL 9.8
TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
TI-2017-04499 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
TI-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8

See all 617 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences