CVE-2015-0646: Cisco IOS

High severity, CVSS 7.8. EPSS: 3.8% chance of exploitation in the next 30 days.

Memory leak in the TCP input module in Cisco IOS 12.2, 12.4, 15.0, 15.2, 15.3, and 15.4 and IOS XE 3.3.xXO, 3.5.xE, 3.6.xE, 3.8.xS through 3.10.xS before 3.10.5S, and 3.11.xS and 3.12.xS before 3.12.3S allows remote attackers to cause a denial of service (memory consumption or device reload) by sending crafted TCP packets over (1) IPv4 or (2) IPv6, aka Bug ID CSCum94811.

Affected products

• Cisco IOS: version 12.2 only; version 12.4 only; version 15.0 only; version 15.1 only; version 15.2 only; version 15.3 only; …
• Cisco IOS XE: version 3.3xo.0 only; version 3.3xo.1 only; version 3.3xo.2 only; version 3.5e.0 only; version 3.5e.1 only; version 3.5e.2 only; …

Published 2015-03-26. Last modified 2026-06-17.