CVE-2011-4667: Cisco IOS

Medium severity, CVSS 5.9. EPSS: 0.7% chance of exploitation in the next 30 days.

The encryption library in Cisco IOS Software 15.2(1)T, 15.2(1)T1, and 15.2(2)T, Cisco NX-OS in Cisco MDS 9222i Multiservice Modular Switch, Cisco MDS 9000 18/4-Port Multiservice Module, and Cisco MDS 9000 Storage Services Node module before 5.2(6), and Cisco IOS in Cisco VPN Services Port Adaptor for Catalyst 6500 12.2(33)SXI, and 12.2(33)SXJ when IP Security (aka IPSec) is used, allows remote attackers to obtain unencrypted packets from encrypted sessions.

Affected products

• Cisco IOS: version 12.2(33)sxi only; version 12.2(33)sxj only; version 15.2(1)t only; version 15.2(1)t1 only; version 15.2(2)t only
• Cisco NX-OS: version 5.0(5) only

Published 2017-09-25. Last modified 2026-06-16.