Ubuntu Security Notice 939-1 - L. Minier discovered that xvfb-run did not correctly keep the X.org session cookie private. A local attacker could gain access to any local sessions started by xvfb-run. Ubuntu 9.10 was not affected. It was discovered that the X.org server did not correctly handle certain calculations. A remote attacker could exploit this to crash the X.org session or possibly run arbitrary code with root privileges.
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