5 - RHSA-2013:1135

Problem Description:

Updated nss and nspr packages that fix two security issues, various bugs, and add enhancements are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

2. Relevant releases/architectures:

RHEL Desktop Workstation (v. 5 client) - i386, x86_64 Red Hat Enterprise Linux (v. 5 server) - i386, ia64, ppc, s390x, x86_64 Red Hat Enterprise Linux Desktop (v. 5 client) - i386, x86_64

3. Description:

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.

It was discovered that NSS leaked timing information when decrypting TLS/SSL and DTLS protocol encrypted records when CBC-mode cipher suites were used. A remote attacker could possibly use this flaw to retrieve plain text from the encrypted packets by using a TLS/SSL or DTLS server as a padding oracle. (CVE-2013-1620)

An out-of-bounds memory read flaw was found in the way NSS decoded certain certificates. If an application using NSS decoded a malformed certificate, it could cause the application to crash. (CVE-2013-0791)

Red Hat would like to thank the Mozilla project for reporting CVE-2013-0791. Upstream acknowledges Ambroz Bizjak as the original reporter of CVE-2013-0791.

This update also fixes the following bugs:

* A defect in the FreeBL library implementation of the Diffie-Hellman (DH) protocol previously caused Openswan to drop connections. (BZ#958023)

* A memory leak in the nssutil_ReadSecmodDB() function has been fixed. (BZ#986969)

In addition, the nss package has been upgraded to upstream version 3.14.3, and the nspr package has been upgraded to upstream version 4.9.5. These updates provide a number of bug fixes and enhancements over the previous versions. (BZ#949845, BZ#924741)

Note that while upstream NSS version 3.14 prevents the use of certificates that have an MD5 signature, this erratum includes a patch that allows such certificates by default. To prevent the use of certificates that have an MD5 signature, set the "NSS_HASH_ALG_SUPPORT" environment variable to "-MD5".

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.

4. Solution:

Before applying this update, make sure all previously released errata relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/site/articles/11258

5. Bugs fixed (http://bugzilla.redhat.com/):

908234 - CVE-2013-1620 nss: TLS CBC padding timing attack 924741 - Rebase to nspr-4.9.5 946947 - CVE-2013-0791 Mozilla: Out-of-bounds array read in CERT_DecodeCertPackage (MFSA 2013-40) 949845 - [RFE][RHEL5] Rebase to nss-3.14.3 to fix the lucky-13 issue 986969 - nssutil_ReadSecmodDB() leaks memory