Phishing

ALSO CALLED: Email Spoofing, e-Mail Fraud, Spear Phishing, Password Phishing, Brand Spoofing, Email Fraud, e-Mail Spoofing, Social Engineering, Internet Phishing, Carding, Password Cracking, Spear-phishing
DEFINITION: E-mail spoofing is the forgery of an e-mail header so that the message appears to have originated from someone or somewhere other than the actual source. Distributors of spam often use spoofing in an attempt to get recipients to open, and possibly even respond to, their solicitations. Spoofing can be used legitimately. Classic examples of senders who might prefer to disguise the source of the e-mail  … 
Definition continues below.

PHISHING DEFINITION (continued): …  include a sender reporting mistreatment by a spouse to a welfare agency or a "whistle-blower" who fears retaliation. However, spoofing anyone other than yourself is illegal in some jurisdictions. E-mail spoofing is possible because Simple Mail Transfer Protocol (SMTP), the main protocol used in sending e-mail, does not include an authentication mechanism. Although an SMTP service extension (specified in IETF RFC 2554) allows an SMTP client to negotiate a security level with a mail server, this precaution is not often taken. If the precaution is not taken, anyone with the requisite knowledge … 
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