Vishing is the unlawful practice of utilizing social engineering over the telephone system, using features of Voice over IP (VoIP) to access confidential personal and financial information from the public for financial reward. The term "vishing" is a combined form of "voice" and "phishing". Vishing takes advantage of the public's trust in using landline telephone systems that end in physical locations recognized by the telephone company, and associated with a paying customer. VoIP makes previously anti-abuse tools or features of caller ID spoofing, complex automated systems (IVR), low cost, and anonymity for the paying customer widely available. Typically, vishing is used to capture credit card numbers or other sensitive information to be used in identity theft schemes by perpetrators. Legal authorities find it difficult to monitor or trace vishing scams, although technology is used to monitor all PSTN based traffic, identifying vishing attempts as a result of patterns and anomalies in call activities. Consumers are advised to be suspicious when they receive messages prompting them to call and give their credit card or bank numbers. Usually, the consumer is directed to contact their bank or credit card company to verify the message.
VoIP spam, is the proliferation of unwanted phone calls that are automatically-dialed with pre-recorded messages using Voice over Internet Protocol (VoIP). Some even call it SPIT which stands for "Spam over Internet Telephony". Email, Internet applications and other Voice over IP systems are vulnerable to abuse by attackers who instigate unsolicited and unwanted communications. Telemarketers, prank callers, and other telephone system abusers are increasingly targeting VoIP. The technology behind this threat is SIP (Session Initiation Protocol, IETF – Internet Engineering Task Force, RFC 3261) which has has been supported by major telecommunication vendors, and could become the industry standard for voice, video and other types of interactive communication including instant messaging and gaming.