RHEL 6 : kernel (RHSA-2014:0900)
High Nessus Plugin ID 79035
SynopsisThe remote Red Hat host is missing one or more security updates.
DescriptionUpdated kernel packages that fix three security issues and one bug are now available for Red Hat Enterprise Linux 6.4 Extended Update Support.
The Red Hat Security Response Team has rated this update as having Important security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.
The kernel packages contain the Linux kernel, the core of any Linux operating system.
* A flaw was found in the way the Linux kernel's futex subsystem handled the requeuing of certain Priority Inheritance (PI) futexes. A local, unprivileged user could use this flaw to escalate their privileges on the system. (CVE-2014-3153, Important)
* A flaw was found in the way the Linux kernel's floppy driver handled user space provided data in certain error code paths while processing FDRAWCMD IOCTL commands. A local user with write access to /dev/fdX could use this flaw to free (using the kfree() function) arbitrary kernel memory. (CVE-2014-1737, Important)
* It was found that the Linux kernel's floppy driver leaked internal kernel memory addresses to user space during the processing of the FDRAWCMD IOCTL command. A local user with write access to /dev/fdX could use this flaw to obtain information about the kernel heap arrangement. (CVE-2014-1738, Low)
Note: A local user with write access to /dev/fdX could use these two flaws (CVE-2014-1737 in combination with CVE-2014-1738) to escalate their privileges on the system.
Red Hat would like to thank Kees Cook of Google for reporting CVE-2014-3153, and Matthew Daley for reporting CVE-2014-1737 and CVE-2014-1738. Google acknowledges Pinkie Pie as the original reporter of CVE-2014-3153.
This update also fixes the following bug :
* A previous change that introduced global clock updates caused guest machines to boot slowly when the host Time Stamp Counter (TSC) was marked as unstable. The slow down increased with the number of vCPUs allocated. To resolve this problem, a patch has been applied to limit the rate of the global clock updates. (BZ#1102253)
All kernel users are advised to upgrade to these updated packages, which contain backported patches to correct these issues. The system must be rebooted for this update to take effect.
SolutionUpdate the affected packages.