RHSA-2008:0896 - Security Advisory

Topic

Updated ruby packages that fix several security issues are now available
for Red Hat Enterprise Linux 3.

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

Description

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.

Solution

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

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/FAQ_58_10188

Affected Products

• Red Hat Enterprise Linux Server 3 x86_64
• Red Hat Enterprise Linux Server 3 ia64
• Red Hat Enterprise Linux Server 3 i386
• Red Hat Enterprise Linux Workstation 3 x86_64
• Red Hat Enterprise Linux Workstation 3 ia64
• Red Hat Enterprise Linux Workstation 3 i386
• Red Hat Enterprise Linux Desktop 3 x86_64
• Red Hat Enterprise Linux Desktop 3 i386
• Red Hat Enterprise Linux for IBM z Systems 3 s390x
• Red Hat Enterprise Linux for IBM z Systems 3 s390
• Red Hat Enterprise Linux for Power, big endian 3 ppc

Fixes

• BZ - 458948 - CVE-2008-3655 ruby: multiple insufficient safe mode restrictions
• BZ - 459266 - CVE-2008-3443 ruby: Memory allocation failure in Ruby regex engine (remotely exploitable DoS)
• BZ - 461495 - CVE-2008-3905 ruby: use of predictable source port and transaction id in DNS requests done by resolv.rb module

CVEs

• CVE-2008-3655
• CVE-2008-3905
• CVE-2008-3443

References

• http://www.redhat.com/security/updates/classification/#moderate