Network traffic encrypted using an RSA-based SSL certificate may be decrypted if enough SSLv2 handshake data can be collected. Exploitation of this vulnerability—referred to as DROWN in public reporting—may allow a remote attacker to decrypt individual messages from a server supporting SSLv2.
US-CERT encourages users and administrators to review Vulnerability Note VU#583776 and the US-CERT OpenSSL Current Activity for additional information and mitigation details.