Synopsis

Critical: firefox security update

Type/Severity

Security Advisory: Critical

Topic

Updated firefox packages that fix several security issues are now available
for Red Hat Enterprise Linux 4, 5, and 6.

The Red Hat Security Response Team has rated this update as having critical
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.

Description

Mozilla Firefox is an open source web browser. XULRunner provides the XUL
Runtime environment for Mozilla Firefox.

Several flaws were found in the processing of malformed web content. A web
page containing malicious content could cause Firefox to crash or,
potentially, execute arbitrary code with the privileges of the user running
Firefox. (CVE-2011-2995)

A flaw was found in the way Firefox processed the "Enter" keypress event. A
malicious web page could present a download dialog while the key is
pressed, activating the default "Open" action. A remote attacker could
exploit this vulnerability by causing the browser to open malicious web
content. (CVE-2011-2372)

A flaw was found in the way Firefox handled Location headers in redirect
responses. Two copies of this header with different values could be a
symptom of a CRLF injection attack against a vulnerable server. Firefox now
treats two copies of the Location, Content-Length, or Content-Disposition
header as an error condition. (CVE-2011-3000)

A flaw was found in the way Firefox handled frame objects with certain
names. An attacker could use this flaw to cause a plug-in to grant its
content access to another site or the local file system, violating the
same-origin policy. (CVE-2011-2999)

An integer underflow flaw was found in the way Firefox handled large
JavaScript regular expressions. A web page containing malicious JavaScript
could cause Firefox to access already freed memory, causing Firefox to
crash or, potentially, execute arbitrary code with the privileges of the
user running Firefox. (CVE-2011-2998)

For technical details regarding these flaws, refer to the Mozilla security
advisories for Firefox 3.6.23. You can find a link to the Mozilla
advisories in the References section of this erratum.

All Firefox users should upgrade to these updated packages, which contain
Firefox version 3.6.23, which corrects these issues. After installing the
update, Firefox must be restarted for the changes to take effect.

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/kb/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Server 4 x86_64
• Red Hat Enterprise Linux Server 4 ia64
• Red Hat Enterprise Linux Server 4 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Workstation 4 ia64
• Red Hat Enterprise Linux Workstation 4 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux Desktop 4 x86_64
• Red Hat Enterprise Linux Desktop 4 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390x
• Red Hat Enterprise Linux for IBM z Systems 4 s390
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.1 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux for Power, big endian 4 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.1 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 i386
• Red Hat Virtual Storage Appliance (from RHUI) 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 4 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

• BZ - 741902 - CVE-2011-2995 Mozilla: Miscellaneous memory safety hazards (MFSA 2011-36)
• BZ - 741904 - CVE-2011-2999 Mozilla: XSS via plugins and shadowed window.location object (MFSA 2011-38)
• BZ - 741905 - CVE-2011-3000 Mozilla:Defense against multiple Location headers due to CRLF Injection (MFSA 2011-39)
• BZ - 741917 - CVE-2011-2372 Mozilla:Code installation through holding down Enter (MFSA 2011-40)
• BZ - 741924 - CVE-2011-2998 Mozilla: Integer underflow when using JavaScript RegExp (MFSA 2011-37)

CVEs

• CVE-2011-2372
• CVE-2011-2995
• CVE-2011-3000
• CVE-2011-2999
• CVE-2011-2998

References