Red Hat EL 3 & 4 RHSA-2009-1083-01 Critical: CUPS DoS Issues

The Common UNIX® Printing System (CUPS) provides a portable printing layer for UNIX operating systems. The Internet Printing Protocol (IPP) allows users to print and manage printing-related tasks over a network. The CUPS "pdftops" filter converts Portable Document Format (PDF) files to PostScript. "pdftops" is based on Xpdf and the CUPS imaging library.
A NULL pointer dereference flaw was found in the CUPS IPP routine, used for processing incoming IPP requests for the CUPS scheduler. An attacker could use this flaw to send specially-crafted IPP requests that would crash the cupsd daemon. (CVE-2009-0949)
A use-after-free flaw was found in the CUPS scheduler directory services routine, used to process data about available printers and printer classes. An attacker could use this flaw to cause a denial of service (cupsd daemon stop or crash). (CVE-2009-1196)
Multiple integer overflows flaws, leading to heap-based buffer overflows, were found in the CUPS "pdftops" filter. An attacker could create a malicious PDF file that would cause "pdftops" to crash or, potentially, execute arbitrary code as the "lp" user if the file was printed. (CVE-2009-0791)
Red Hat would like to thank Anibal Sacco from Core Security Technologies for reporting the CVE-2009-0949 flaw, and Swen van Brussel for reporting the CVE-2009-1196 flaw.
Users of cups are advised to upgrade to these updated packages, which contain backported patches to correct these issues. After installing this update, the cupsd daemon will be restarted automatically.