Updated systemtap packages that fix two security issues are now available for Red Hat Enterprise Linux 5 and 6.
The Red Hat Security Response Team has rated this update as having important security impact. Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) associated with each description below.
SystemTap is an instrumentation system for systems running the Linux kernel, version 2.6. Developers can write scripts to collect data on the operation of the system. staprun, the SystemTap runtime tool, is used for managing SystemTap kernel modules (for example, loading them).
It was discovered that staprun did not properly sanitize the environment before executing the modprobe command to load an additional kernel module. A local, unprivileged user could use this flaw to escalate their privileges.
It was discovered that staprun did not check if the module to be unloaded was previously loaded by SystemTap. A local, unprivileged user could use this flaw to unload an arbitrary kernel module that was not in use.
Note: After installing this update, users already in the stapdev group must be added to the stapusr group in order to be able to run the staprun tool.
Red Hat would like to thank Tavis Ormandy for reporting these issues.
SystemTap users should upgrade to these updated packages, which contain backported patches to correct these issues.