(RHSA-2013:1779) Moderate: mod_nss security update

The mod_nss module provides strong cryptography for the Apache HTTP Server
via the Secure Sockets Layer (SSL) and Transport Layer Security (TLS)
protocols, using the Network Security Services (NSS) security library.

A flaw was found in the way mod_nss handled the NSSVerifyClient setting for
the per-directory context. When configured to not require a client
certificate for the initial connection and only require it for a specific
directory, mod_nss failed to enforce this requirement and allowed a client
to access the directory when no valid client certificate was provided.
(CVE-2013-4566)

Red Hat would like to thank Albert Smith of OUSD(AT&L) for reporting this
issue.

All mod_nss users should upgrade to this updated package, which contains a
backported patch to correct this issue. The httpd service must be restarted
for this update to take effect.