Issued:
2013-03-06
Updated:
2013-03-06

RHSA-2013:0566 - Important: kernel-rt security and bug fix update

Synopsis

Important: kernel-rt security and bug fix update

Type/Severity

Security Advisory Important

Topic

Updated kernel-rt packages that fix several security issues and multiple bugs are now available for Red Hat Enterprise MRG 2.3.

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.

Description

The kernel-rt packages contain the Linux kernel, the core of any Linux operating system.

This update fixes the following security issues:

  • A buffer overflow flaw was found in the way UTF-8 characters were converted to UTF-16 in the utf8s_to_utf16s() function of the Linux kernel's FAT file system implementation. A local user able to mount a FAT file system with the "utf8=1" option could use this flaw to crash the system or, potentially, to escalate their privileges. (CVE-2013-1773, Important)

  • It was found that the RHSA-2012:0333 update did not correctly fix the CVE-2011-4131 issue. A malicious Network File System version 4 (NFSv4) server could return a crafted reply to a GETACL request, causing a denial of service on the client. (CVE-2012-2375, Moderate)

  • A memory disclosure flaw was found in the way the load_script() function in the binfmt_script binary format handler handled excessive recursions. A local, unprivileged user could use this flaw to leak kernel stack memory to user-space by executing specially-crafted scripts. (CVE-2012-4530, Low)

  • A flaw was found in the way file permission checks for the "/dev/kmsg" file were performed in restricted root environments (for example, when using a capability-based security model). A local user able to write to this file could cause a denial of service. (CVE-2013-1772, Low)

The CVE-2012-2375 issue was discovered by Jian Li of Red Hat.

This update also fixes multiple bugs. Documentation for these changes will be available shortly from the Technical Notes document linked to in the References section.

Users should upgrade to these updated packages, which upgrade the kernel-rt kernel to version kernel-rt-3.6.11-rt28, correct these issues, and fix the bugs noted in the Red Hat Enterprise MRG 2 Technical Notes. The system must be rebooted for this update to take effect.

Solution

Before applying this update, make sure all previously-released errata relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/knowledge/articles/11258

To install kernel packages manually, use "rpm -ivh [package]". Do not use "rpm -Uvh" as that will remove the running kernel binaries from your system. You may use "rpm -e" to remove old kernels after determining that the new kernel functions properly on your system.

Affected Products

ProductVersionArch
MRG Realtime2x86_64

Updated Packages

  • kernel-rt-doc-3.6.11-rt28.20.el6rt.noarch.rpm
  • kernel-rt-debug-devel-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-debug-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-firmware-3.6.11-rt28.20.el6rt.noarch.rpm
  • kernel-rt-debuginfo-common-x86_64-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-trace-debuginfo-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-3.6.11-rt28.20.el6rt.src.rpm
  • mrg-rt-release-3.6.11-rt28.20.el6rt.noarch.rpm
  • kernel-rt-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-debuginfo-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-vanilla-debuginfo-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-debug-debuginfo-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-vanilla-devel-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-devel-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-vanilla-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-trace-3.6.11-rt28.20.el6rt.x86_64.rpm
  • kernel-rt-trace-devel-3.6.11-rt28.20.el6rt.x86_64.rpm

Fixes

CVEs

References

Additional information