The kernel packages contain the Linux kernel, the core of any Linux operating system. This update fixes the following security issue: * when an application has a stack overflow, the stack could silently overwrite another memory mapped area instead of a segmentation fault occurring, which could cause an application to execute arbitrary code, possibly leading to privilege escalation. It is known that the X Window System server can be used to trigger this flaw. Red Hat would like to thank the X.Org security team for reporting this issue. Upstream acknowledges Rafal Wojtczuk as the original reporter. Users should upgrade to these updated packages, which contain backported patches to correct this issue. The system must be rebooted for this update to take effect.