The kernel in CentOS Linux Advanced Server 2.1 is vulnerable to a local denial of service attack. Updated packages are available which address this vulnerability. [Updated 28 August 2003] Added CAN-2003-0461 to the list of security issues that were fixed by this advisory (there are no changes to the packages themselves).
The Linux kernel handles the basic functions of the operating system. A vulnerability in the Linux kernel has been discovered in which a non-root user can cause the machine to freeze. This kernel addresses the vulnerability. Note: This bug is specific to the x86 architecture kernels only, and does not affect ia64 or other architectures. In addition, /proc/tty/driver/serial reveals the exact number of characters used in serial links, which could allow local users to obtain potentially sensitive information such as password lengths. All users should upgrade to these errata packages, which are not vulnerable to these issues. Thanks go to Christopher Devine for reporting the vulnerability on Bugtraq, and Petr Vandrovec for being the first to supply a fix to the community.