ROBOT exploit from 1998 resurrected, leaves top websites' crypto vulnerable ZDNet

A number of the most popular websites and services online, including Facebook and PayPal, are vulnerable to an exploit which has resurfaced from 1998. The security flaw, dubbed ROBOT, was first discovered almost two decades ago by Daniel Bleichenbacher. PKCS #1 1.5 padding error messages produced by secure sockets layer (SSL) servers allow for an adaptive-chosen ciphertext attack which "fully breaks the confidentiality of TLS when used with RSA encryption," according to researchers Hanno Böck and Juraj Somorovsky from Hackmanit GmbH, Ruhr-Universität Bochum, and Tripwire VERT's Craig Young. The server implementation bug could be used to perform RSA decryption and key signing in order to decrypt traffic. "We discovered that by using some slight variations this vulnerability can still be used against many HTTPS hosts in today's Internet," the team says.