Two researchers have developed a new attack on TLS 1.0/SSL 3.0 that enables them to decrypt client requests on the fly and hijack supposedly confidential sessions with sensitive sites such as online banking, e-commerce and payment sites. The attack breaks the confidentiality model of the protocol and is the first known exploitation of a long-known flaw in TLS, potentially affecting the security of transactions on millions of sites.
There is quite a bit of alarming data in what the project has gathered, and one of those pieces of information is that more than 148,000 of the sites surveyed are vulnerable to the BEAST attack, which was developed by researchers Juliano Rizzo and Thai Duong and disclosed last year. Their attack uses what's known as a chosen-plaintext attack against the AES implementation in the TLS 1.0 protocol and enables them to use a custom tool they wrote to steal and decrypt supposedly secure HTTPS cookies. The attacker can then hijack the victim's secure SSL session with a site such as an e-commerce site or online banking site.