Ubuntu Security Notice 1990-1 – Pedro Ribeiro discovered that the X.Org X server incorrectly handled memory operations when handling ImageText requests. An attacker could use this issue to cause X.Org to crash, or to possibly execute arbitrary code. It was discovered that non-root X.Org X servers such as Xephyr incorrectly used cached xkb files. A local attacker could use this flaw to cause a xkb cache file to be loaded by another user, resulting in a denial of service. Various other issues were also addressed…. Ubuntu Security Notice 1990-1 – Pedro Ribeiro discovered that the X.Org X server incorrectly handled memory operations when handling ImageText requests. An attacker could use this issue to cause X.Org to crash, or to possibly execute arbitrary code. It was discovered that non-root X.Org X servers such as Xephyr incorrectly used cached xkb files. A local attacker could use this flaw to cause a xkb cache file to be loaded by another user, resulting in a denial of service. Various other issues were also addressed.

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