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Ubuntu Security Notice USN-3076-1
September 22, 2016

firefox vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS
- Ubuntu 12.04 LTS

Summary:

Firefox could be made to crash or run programs as your login if it
opened a malicious website.

Software Description:
- firefox: Mozilla Open Source web browser

Details:

Atte Kettunen discovered an out-of-bounds read when handling certain
Content Security Policy (CSP) directives in some circumstances. If a user
were tricked in to opening a specially crafted website, an attacker could
potentially exploit this to cause a denial of service via application
crash. (CVE-2016-2827)

Christoph Diehl, Christian Holler, Gary Kwong, Nathan Froyd, Honza Bambas,
Seth Fowler, Michael Smith, Andrew McCreight, Dan Minor, Byron Campen, Jon
Coppeard, Steve Fink, Tyson Smith, and Carsten Book discovered multiple
memory safety issues in Firefox. If a user were tricked in to opening a
specially crafted website, an attacker could potentially exploit these to
cause a denial of service via application crash, or execute arbitrary
code. (CVE-2016-5256, CVE-2016-5257)

Atte Kettunen discovered a heap buffer overflow during text conversion
with some unicode characters. If a user were tricked in to opening a
specially crafted website, an attacker could potentially exploit this to
cause a denial of service via application crash, or execute arbitrary
code. (CVE-2016-5270)

Abhishek Arya discovered an out of bounds read during the processing of
text runs in some circumstances. If a user were tricked in to opening a
specially crafted website, an attacker could potentially exploit this to
cause a denial of service via application crash. (CVE-2016-5271)

Abhishek Arya discovered a bad cast when processing layout with input
elements in some circumstances. If a user were tricked in to opening a
specially crafted website, an attacker could potentially exploit this to
cause a denial of service via application crash, or execute arbitrary
code. (CVE-2016-5272)

A crash was discovered in accessibility. If a user were tricked in to
opening a specially crafted website, an attacker could potentially
exploit this to execute arbitrary code. (CVE-2016-5273)

A use-after-free was discovered in web animations during restyling. If a
user were tricked in to opening a specially crafted website, an attacker
could potentially exploit this to cause a denial of service via
application crash, or execute arbitrary code. (CVE-2016-5274)

A buffer overflow was discovered when working with empty filters during
canvas rendering. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service via application crash, or execute arbitrary code. (CVE-2016-5275)

A use-after-free was discovered in accessibility. If a user were tricked
in to opening a specially crafted website, an attacker could potentially
exploit this to cause a denial of service via application crash, or
execute arbitrary code. (CVE-2016-5276)

A use-after-free was discovered in web animations when destroying a
timeline. If a user were tricked in to opening a specially crafted
website, an attacker could potentially exploit this to cause a denial of
service via application crash, or execute arbitrary code. (CVE-2016-5277)

A buffer overflow was discovered when encoding image frames to images in
some circumstances. If a user were tricked in to opening a specially
crafted website, an attacker could potentially exploit this to cause a
denial of service via application crash, or execute arbitrary code.
(CVE-2016-5278)

Rafael Gieschke discovered that the full path of files is available to web
pages after a drag and drop operation. An attacker could potentially
exploit this to obtain sensitive information. (CVE-2016-5279)

Mei Wang discovered a use-after-free when changing text direction. If a
user were tricked in to opening a specially crafted website, an attacker
could potentially exploit this to cause a denial of service via
application crash, or execute arbitrary code. (CVE-2016-5280)

Brian Carpenter discovered a use-after-free when manipulating SVG content
in some circumstances. If a user were tricked in to opening a specially
crafted website, an attacker could potentially exploit this to cause a
denial of service via application crash, or execute arbitrary code.
(CVE-2016-5281)

Richard Newman discovered that favicons can be loaded through
non-whitelisted protocols, such as jar:. (CVE-2016-5282)

Gavin Sharp discovered a timing attack vulnerability involving document
resizes and link colours. If a user were tricked in to opening a specially
crafted website, an attacker could potentially exploit this to obtain
sensitive information. (CVE-2016-5283)

An issue was discovered with the preloaded Public Key Pinning (HPKP). If
a man-in-the-middle (MITM) attacker was able to obtain a fraudulent
certificate for a Mozilla site, they could exploit this by providing
malicious addon updates. (CVE-2016-5284)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 16.04 LTS:
  firefox                         49.0+build4-0ubuntu0.16.04.1

Ubuntu 14.04 LTS:
  firefox                         49.0+build4-0ubuntu0.14.04.1

Ubuntu 12.04 LTS:
  firefox                         49.0+build4-0ubuntu0.12.04.1

After a standard system update you need to restart Firefox to make
all the necessary changes.

References:
  http://www.ubuntu.com/usn/usn-3076-1
  CVE-2016-2827, CVE-2016-5256, CVE-2016-5257, CVE-2016-5270,
  CVE-2016-5271, CVE-2016-5272, CVE-2016-5273, CVE-2016-5274,
  CVE-2016-5275, CVE-2016-5276, CVE-2016-5277, CVE-2016-5278,
  CVE-2016-5279, CVE-2016-5280, CVE-2016-5281, CVE-2016-5282,
  CVE-2016-5283, CVE-2016-5284

Package Information:
  https://launchpad.net/ubuntu/+source/firefox/49.0+build4-0ubuntu0.16.04.1
  https://launchpad.net/ubuntu/+source/firefox/49.0+build4-0ubuntu0.14.04.1
  https://launchpad.net/ubuntu/+source/firefox/49.0+build4-0ubuntu0.12.04.1