Cisco Devices are not effected as they are running OpenSSL version 0.9.8 on the newest 9.01 IOS Software. Most Cisco Firewalls have Older IOS versions and therefore have older versions of OpenSSL.

The heartbleed bug was introduced in OpenSSL 1.0.1 and is present in
• 1.0.1
• 1.0.1a
• 1.0.1b
• 1.0.1c
• 1.0.1d
• 1.0.1e
• 1.0.1f
The bug is not present in 1.0.1g, nor is it present in the 1.0.0 branch nor the 0.9.8 branch of OpenSSL.