Red Hat Enterprise Linux 5: RHSA-2013:1791-01 Important NSS/NSPR Update

Network Security Services (NSS) is a set of libraries designed to support the cross-platform development of security-enabled client and server applications. Netscape Portable Runtime (NSPR) provides platform independence for non-GUI operating system facilities.
A flaw was found in the way NSS handled invalid handshake packets. A remote attacker could use this flaw to cause a TLS/SSL client using NSS to crash or, possibly, execute arbitrary code with the privileges of the user running the application. (CVE-2013-5605)
It was found that the fix for CVE-2013-1620 released via RHSA-2013:1135 introduced a regression causing NSS to read uninitialized data when a decryption failure occurred. A remote attacker could use this flaw to cause a TLS/SSL server using NSS to crash. (CVE-2013-1739)
An integer overflow flaw was discovered in both NSS and NSPR's implementation of certification parsing on 64-bit systems. A remote attacker could use these flaws to cause an application using NSS or NSPR to crash. (CVE-2013-1741, CVE-2013-5607)
It was discovered that NSS did not reject certificates with incompatible key usage constraints when validating them while the verifyLog feature was enabled. An application using the NSS certificate validation API could accept an invalid certificate. (CVE-2013-5606)
Red Hat would like to thank the Mozilla project for reporting CVE-2013-1741, CVE-2013-5606, and CVE-2013-5607. Upstream acknowledges Tavis Ormandy as the original reporter of CVE-2013-1741, Camilo Viecco as the original reporter of CVE-2013-5606, and Pascal Cuoq, Kamil Dudka, and Wan-Teh Chang as the original reporters of CVE-2013-5607.
In addition, the nss package has been upgraded to upstream version 3.15.3, and the nspr package has been upgraded to upstream version 4.10.2. These updates provide a number of bug fixes and enhancements over the previous versions. (BZ#1033478, BZ#1020520)
This update also fixes the following bug:
* The RHBA-2013:1318 update introduced a regression that prevented the use of certificates that have an MD5 signature. This update fixes this regression and certificates that have an MD5 signature are once again supported. To prevent the use of certificates that have an MD5 signature, set the "NSS_HASH_ALG_SUPPORT" environment variable to "-MD5". (BZ#1033499)
Users of NSS and NSPR are advised to upgrade to these updated packages, which fix these issues and add these enhancements. After installing this update, applications using NSS or NSPR must be restarted for this update to take effect.