RedHat Security Advisory RHSA-2009:1438

The remote host is missing updates to the Linux kernel announced in advisory RHSA-2009:1438. This update fixes the following security issues: * the ADDR_COMPAT_LAYOUT and MMAP_PAGE_ZERO flags were not cleared when a setuid or setgid program was executed. A local, unprivileged user could use this flaw to bypass the mmap_min_addr protection mechanism and perform a NULL pointer dereference attack, or bypass the Address Space Layout Randomization (ASLR) security feature. (CVE-2009-1895, Important) * it was discovered that, when executing a new process, the clear_child_tid pointer in the Linux kernel is not cleared. If this pointer points to a writable portion of the memory of the new program, the kernel could corrupt four bytes of memory, possibly leading to a local denial of service or privilege escalation. (CVE-2009-2848, Important) * Solar Designer reported a missing capability check in the z90crypt driver in the Linux kernel. This missing check could allow a local user with an effective user ID (euid) of 0 to bypass intended capability restrictions. (CVE-2009-1883, Moderate) * a flaw was found in the way the do_sigaltstack() function in the Linux kernel copies the stack_t structure to user-space. On 64-bit machines, this flaw could lead to a four-byte information leak. (CVE-2009-2847, Moderate)
Please note that this update is available via Red Hat Network. To use Red Hat Network, launch the Red Hat Update Agent with the following command: up2date