The utrace support in Linux kernel 2.6.18, and other versions, allows local users to cause a denial of service (system hang) related to "MT exec + utrace_attach spin failure mode," as demonstrated by ptrace-thrash.c.

Updated kernel packages that fix security issues and bugs in the Red Hat Enterprise Linux 5 kernel are now available.

This update has been rated as having important security impact by the Red Hat Security Response Team.

The Linux kernel handles the basic functions of the operating system.

These new kernel packages contain fixes for the following security issues :

* a flaw in the IPv6 socket option handling that allowed a local user to read arbitrary kernel memory (CVE-2007-1000, Important).

* a flaw in the IPv6 socket option handling that allowed a local user to cause a denial of service (CVE-2007-1388, Important).

* a flaw in the utrace support that allowed a local user to cause a denial of service (CVE-2007-0771, Important).

In addition to the security issues described above, a fix for a memory leak in the audit subsystem and a fix for a data corruption bug on s390 systems have been included.

Red Hat Enterprise Linux 5 users are advised to upgrade to these erratum packages, which are not vulnerable to these issues.

The remote CentOS system is missing a security update which has been documented in Red Hat advisory RHSA-2007-0169.

ID	Name	Product	Family	Severity
25328	RHEL 5 : kernel (RHSA-2007:0169)	Nessus	Red Hat Local Security Checks	high
25126	CentOS 5 : Kernel (CESA-2007:0169)	Nessus	CentOS Local Security Checks	high
801426	CentOS RHSA-2007-0169 Security Check	Log Correlation Engine	Generic	high

Detections

Analytics

CVE-2007-0771

medium

Tenable Plugins

high

high

high