irb, ruby security update

CentOS Errata and Security Advisory CESA-2008:0896

Ruby is an interpreted scripting language for quick and easy
object-oriented programming.

The Ruby DNS resolver library, resolv.rb, used predictable transaction IDs
and a fixed source port when sending DNS requests. A remote attacker could
use this flaw to spoof a malicious reply to a DNS query. (CVE-2008-3905)

A number of flaws were found in the safe-level restrictions in Ruby. It
was possible for an attacker to create a carefully crafted malicious script
that can allow the bypass of certain safe-level restrictions. (CVE-2008-3655)

A denial of service flaw was found in Ruby’s regular expression engine. If
a Ruby script tried to process a large amount of data via a regular
expression, it could cause Ruby to enter an infinite-loop and crash.
(CVE-2008-3443)

Users of ruby should upgrade to these updated packages, which contain
backported patches to resolve these issues.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2008-October/077494.html
https://lists.centos.org/pipermail/centos-announce/2008-October/077495.html
https://lists.centos.org/pipermail/centos-announce/2008-October/077505.html
https://lists.centos.org/pipermail/centos-announce/2008-October/077509.html

Affected packages:
irb
ruby
ruby-devel
ruby-docs
ruby-libs
ruby-mode
ruby-tcltk

Upstream details at:
https://access.redhat.com/errata/RHSA-2008:0896