7.6 Ensure Insecure SSL Renegotiation Is Not Enabled

Information

A man-in-the-middle renegotiation attack was discovered in SSLv3 and TLSv1 in November, 2009 (CVE-2009-3555). First, a work around and then a fix was approved as an Internet Standard as RFC 574, Feb 2010. The work around, which removes the renegotiation, is available from OpenSSL as of version 0.9.8l and newer versions. For details: https://www.openssl.org/news/secadv_20091111.txt The SSLInsecureRenegotiation directive was added in Apache 2.2.15, for web servers linked with OpenSSL version 0.9.8m or later, to provide backward compatibility to clients with the older, unpatched SSL implementations.

Rationale:

Enabling the SSLInsecureRenegotiation directive leaves the server vulnerable to man-in-the-middle renegotiation attack. Therefore, the SSLInsecureRenegotiation directive should not be enabled.

Solution

Perform the following to implement the recommended state:

Search the Apache configuration files for the SSLInsecureRenegotiation directive. If the directive is present modify the value to be off. If the directive is not present then no action is required.

SSLInsecureRenegotiation off

Default Value:

SSLInsecureRenegotiation off

See Also

https://workbench.cisecurity.org/files/3021