Short Name |
SSL:AUDIT:KEY-RENEGOTIATION |
---|---|
Severity |
Medium |
Recommended |
Yes |
Category |
SSL |
Keywords |
SSL key renegotiation |
Release Date |
2009/09/02 |
Update Number |
1496 |
Supported Platforms |
idp-4.0.110090831+, j-series-9.5+, mx-9.4+, srx-9.2+, srx-branch-9.4+, vsrx-12.1+ |
This protocol anomaly triggers when it detects SSL renegotiation. SSL renegotiation is a new SSL handshake in an established SSL session (with the existing tcp connection). It is encrypted and sent over an existing SSL session. Renegotiation is useful when either/both of the participants want to use different set of keys or hash algorithms and for client authentication over secure connections. According to the 2009 OpenSSL source change log (11/05/2009): Disabling renegotiation completely fixes a severe security problem (CVE-2009-3555), but at the cost of breaking all renegotiations.
Multiple vendors' TLS protocol implementations are prone to a security vulnerability related to the session-renegotiation process. Successful exploits of this issue may allow attackers to perform limited man-in-the-middle attacks against vulnerable applications. Note that this issue does not allow attackers to decrypt encrypted data.