Mike Hommey uploaded new packages for iceweasel which fixed the
following security problems:

CVE-2010-1585
   Roberto Suggi Liverani discovered that the sanitising performed by
   ParanoidFragmentSink was incomplete.

CVE-2011-0053
   Crashes in the layout engine may lead to the execution of arbitrary
   code.

CVE-2011-0051
   Zach Hoffmann discovered that incorrect parsing of recursive eval()
   calls could lead to attackers forcing acceptance of a confirmation
   dialogue.

CVE-2011-0054, CVE-2010-0056
   Christian Holler discovered buffer overflows in the Javascript
   engine, which could allow the execution of arbitrary code.

CVE-2011-0055
   "regenrecht" and Igor Bukanov discovered a use-after-free error in
   the JSON-Implementation, which could lead to the execution of
   arbitrary code.

CVE-2011-0057
   Daniel Kozlowski discovered that incorrect memory handling the web
   workers implementation could lead to the execution of arbitrary
   code.

CVE-2011-0059
   Peleus Uhley discovered a cross-site request forgery risk in the
   plugin code.

For the lenny-backports distribution the problems have been fixed in
version 3.5.16-5~bpo50+1.

For the oldstable distribution (lenny), this problem has been fixed in
version 1.9.0.19-8 of the xulrunner source package.

For the stable distribution (squeeze), this problem has been fixed in
version 3.5.16-5.

For the unstable distribution (sid), this problem has been fixed in
version 3.5.17-1.

Upgrade instructions
--------------------

If you don't use pinning (see [1]) you have to update the package
manually via "apt-get -t lenny-backports install <packagelist>" with
the packagelist of your installed packages affected by this update.
[1] <https://backports.debian.org/Instructions>

We recommend to pin (in /etc/apt/preferences) the backports repository
to 200 so that new versions of installed  backports will be installed
automatically.

  Package: *
  Pin: release a=lenny-backports
  Pin-Priority: 200