RHEL 6 : MRG (RHSA-2014:0439)
Critical Nessus Plugin ID 76674
SynopsisThe remote Red Hat host is missing one or more security updates.
DescriptionUpdated kernel-rt packages that fix multiple security issues, several bugs, and add various enhancements are now available for Red Hat Enterprise MRG 2.5.
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-rt packages contain the Linux kernel, the core of any Linux operating system.
* A denial of service flaw was found in the way the Linux kernel's IPv6 implementation processed IPv6 router advertisement (RA) packets. An attacker able to send a large number of RA packets to a target system could potentially use this flaw to crash the target system.
* A flaw was found in the way the Linux kernel's netfilter connection tracking implementation for Datagram Congestion Control Protocol (DCCP) packets used the skb_header_pointer() function. A remote attacker could use this flaw to send a specially crafted DCCP packet to crash the system or, potentially, escalate their privileges on the system. (CVE-2014-2523, Important)
* A flaw was found in the way the Linux kernel's CIFS implementation handled uncached write operations with specially crafted iovec structures. An unprivileged local user with access to a CIFS share could use this flaw to crash the system, leak kernel memory, or, potentially, escalate their privileges on the system.
* A flaw was found in the way the Linux kernel handled pending Floating Pointer Unit (FPU) exceptions during the switching of tasks. A local attacker could use this flaw to terminate arbitrary processes on the system, causing a denial of service, or, potentially, escalate their privileges on the system. Note that this flaw only affected systems using AMD CPUs on both 32-bit and 64-bit architectures. (CVE-2014-1438, Moderate)
* It was found that certain protocol handlers in the Linux kernel's networking implementation could set the addr_len value without initializing the associated data structure. A local, unprivileged user could use this flaw to leak kernel stack memory to user space using the recvmsg, recvfrom, and recvmmsg system calls.
(CVE-2013-7263, CVE-2013-7265, Low)
* An information leak flaw was found in the Linux kernel's netfilter connection tracking IRC NAT helper implementation that could allow a remote attacker to disclose portions of kernel stack memory during IRC DCC (Direct Client-to-Client) communication over NAT.
* A denial of service flaw was discovered in the way the Linux kernel's SELinux implementation handled files with an empty SELinux security context. A local user who has the CAP_MAC_ADMIN capability could use this flaw to crash the system. (CVE-2014-1874, Low)
This update also fixes several bugs and adds multiple enhancements.
Documentation for these changes will be available shortly from the Technical Notes document linked to in the References section.
Users are advised to upgrade to these updated packages, which upgrade the kernel-rt kernel to version kernel-rt-3.10.33-rt32.33, correct these issues, and fix the bugs and add the enhancements noted in the Red Hat Enterprise MRG 2 Technical Notes. The system must be rebooted for this update to take effect.
SolutionUpdate the affected packages.