Don't be "very, very afraid." Just know what potential dangers lurk out there.
An article in Light Readingdescribes a recently discovered Cisco Internetwork Operating System (IOS) security flaw, and how the flaw could lead to denial-of-service attacks across Cisco-enabled VoIPnetworks.
If you want to learn more about this specific issue, read the Cisco Security Advisory entitled Vulnerability in Cisco IOS Embedded Call Processing Solutions.
Would these risks cause you pause before you implement VoIP? Post a TalkBack.