Twitter Security Hole Left Accounts Open to Hijack Accounts open to anyone to hijack Twitter accounts. Twitter has fixed a vulnerability that allowed users to create fake posts on other users’ Twitter pages. The vulnerability was discovered by a security researcher and author of the book “Phishing Exposed” In April 2007, security researcher Nitesh Dhanjani wrote about a nearly identical threat to Twitter via SMS spoofing. Twitter provides a series of international numbers that can be used to send tweets to non-U.S. users.”]
Source: http://voices.washingtonpost.com/securityfix/2009/03/twitter_security_h.html