5 - RHSA-2005:800

Problem Description:

Updated OpenSSL packages that fix various security issues are now available.

This update has been rated as having moderate security impact by the Red Hat Security Response Team.

2. Relevant releases/architectures:

Red Hat Enterprise Linux AS (Advanced Server) version 2.1 - i386, ia64 Red Hat Linux Advanced Workstation 2.1 - ia64 Red Hat Enterprise Linux ES version 2.1 - i386 Red Hat Enterprise Linux WS version 2.1 - i386 Red Hat Enterprise Linux AS version 3 - i386, ia64, ppc, s390, s390x, x86_64 Red Hat Desktop version 3 - i386, x86_64 Red Hat Enterprise Linux ES version 3 - i386, ia64, x86_64 Red Hat Enterprise Linux WS version 3 - i386, ia64, x86_64 Red Hat Enterprise Linux AS version 4 - i386, ia64, ppc, s390, s390x, x86_64 Red Hat Enterprise Linux Desktop version 4 - i386, x86_64 Red Hat Enterprise Linux ES version 4 - i386, ia64, x86_64 Red Hat Enterprise Linux WS version 4 - i386, ia64, x86_64

3. Problem description:

OpenSSL is a toolkit that implements Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols as well as a full-strength general purpose cryptography library.

OpenSSL contained a software work-around for a bug in SSL handling in Microsoft Internet Explorer version 3.0.2. This work-around is enabled in most servers that use OpenSSL to provide support for SSL and TLS. Yutaka Oiwa discovered that this work-around could allow an attacker, acting as a "man in the middle" to force an SSL connection to use SSL 2.0 rather than a stronger protocol such as SSL 3.0 or TLS 1.0. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2005-2969 to this issue.

A bug was also fixed in the way OpenSSL creates DSA signatures. A cache timing attack was fixed in RHSA-2005-476 which caused OpenSSL to do private key calculations with a fixed time window. The DSA fix for this was not complete and the calculations are not always performed within a fixed-window. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2005-0109 to this issue.

Users are advised to upgrade to these updated packages, which remove the MISE 3.0.2 work-around and contain patches to correct these issues.

Note: After installing this update, users are advised to either restart all services that use OpenSSL or restart their system.

4. Solution:

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

This update is available via Red Hat Network. To use Red Hat Network, launch the Red Hat Update Agent with the following command:

up2date

This will start an interactive process that will result in the appropriate RPMs being upgraded on your system.

5. Bug IDs fixed (http://bugzilla.redhat.com/):

169863 - CAN-2005-2969 Potential SSL 2.0 Rollback 170036 - CAN-2005-0109 DSA signing not quite constant time