Red Hat Training

A Red Hat training course is available for Red Hat Enterprise Linux

4.40. hypervkvpd

An updated hypervkvpd package that fixes one security issue and one bug is now available for Red Hat Enterprise Linux 5.
The Red Hat Security Response Team has rated this update as having low security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link associated with the description below.
The hypervkvpd package contains hypervkvpd, the guest Microsoft Hyper-V Key-Value Pair (KVP) daemon. The daemon passes basic information to the host through VMBus, such as the guest IP address, fully qualified domain name, operating system name, and operating system release number.

Security Fix

A denial of service flaw was found in the way hypervkvpd processed certain Netlink messages. A local, unprivileged user in a guest (running on Microsoft Hyper-V) could send a Netlink message that, when processed, would cause the guest's hypervkvpd daemon to exit.
The CVE-2012-5532 issue was discovered by Florian Weimer of the Red Hat Product Security Team.

Bug Fix

The hypervkvpd daemon did not close the file descriptors for pool files when they were updated. This could eventually lead to hypervkvpd crashing with a "KVP: Failed to open file, pool: 1" error after consuming all available file descriptors. With this update, the file descriptors are closed, correcting this issue.
Users of hypervkvpd are advised to upgrade to this updated package, which contains backported patches to correct these issues. After installing the update, it is recommended to reboot all guest machines.