(RHSA-2010:0651) Moderate: spice-xpi security and bug fix update

The Simple Protocol for Independent Computing Environments (SPICE) is a
remote display protocol used in Red Hat Enterprise Linux for viewing
virtualized guests running on the Kernel-based Virtual Machine (KVM)
hypervisor, or on Red Hat Enterprise Virtualization Hypervisor.

The spice-xpi package provides a plug-in that allows the SPICE client to
run from within Mozilla Firefox.

A race condition was found in the way the SPICE Firefox plug-in and the
SPICE client communicated. A local attacker could use this flaw to trick
the plug-in and the SPICE client into communicating over an
attacker-controlled socket, possibly gaining access to authentication
details, or resulting in a man-in-the-middle attack on the SPICE
connection. (CVE-2010-2792)

It was found that the SPICE Firefox plug-in used a predictable name for its
log file. A local attacker could use this flaw to conduct a symbolic link
attack, allowing them to overwrite arbitrary files accessible to the user
running Firefox. (CVE-2010-2794)

This update also fixes the following bugs:

• a bug prevented users of Red Hat Enterprise Linux 5.5, with all updates
  applied, from running the SPICE Firefox plug-in when using Firefox 3.6.4.
  With this update, the plug-in works correctly with Firefox 3.6.4 and the
  latest version in Red Hat Enterprise Linux 5.5, Firefox 3.6.7. (BZ#618244)

• unused code has been removed during source code refactoring. This also
  resolves a bug in the SPICE Firefox plug-in that caused it to close random
  file descriptors. (BZ#594006, BZ#619067)

Note: This update should be installed together with the RHSA-2010:0632
qspice-client update: https://rhn.redhat.com/errata/RHSA-2010-0632.html

Users of spice-xpi should upgrade to this updated package, which contains
backported patches to correct these issues. After installing the update,
Firefox must be restarted for the changes to take effect.