The Linux kernel handles the basic functions of the operating system.
This advisory includes fixes for several security issues:
Petr Vandrovec discovered a flaw in the 32bit emulation code affecting the Linux 2.4 kernel on the AMD64 architecture. A local attacker could use this flaw to gain privileges. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-1144 to this issue.
ISEC security research discovered multiple vulnerabilities in the IGMP functionality which was backported in the Red Hat Enterprise Linux 3 kernels. These flaws could allow a local user to cause a denial of service (crash) or potentially gain privileges. Where multicast applications are being used on a system, these flaws may also allow remote users to cause a denial of service. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-1137 to this issue.
ISEC security research and Georgi Guninski independantly discovered a flaw in the scm_send function in the auxiliary message layer. A local user could create a carefully crafted auxiliary message which could cause a denial of service (system hang). The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-1016 to this issue.
A floating point information leak was discovered in the ia64 architecture context switch code. A local user could use this flaw to read register values of other processes by setting the MFH bit. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-0565 to this issue.
Kirill Korotaev found a flaw in load_elf_binary affecting kernels prior to 2.4.26. A local user could create a carefully crafted binary in such a way that it would cause a denial of service (system crash). The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-1234 to this issue.
These packages also fix issues in the io_edgeport driver, and a memory leak in ip_options_get.
Note: The kernel-unsupported package contains various drivers and modules that are unsupported and therefore might contain security problems that have not been addressed.
All Red Hat Enterprise Linux 3 users are advised to upgrade their kernels to the packages associated with their machine architectures and configurations as listed in this erratum.