10 - RHSA-2005:053

Problem Description:

Updated CUPS packages that fix several security issues are now available.

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

2. Relevant releases/architectures:

Red Hat Enterprise Linux AS version 4 - i386, ia64, ppc, s390, s390x, x86_64 Red Hat Enterprise Linux Desktop version 4 - i386, x86_64 Red Hat Enterprise Linux ES version 4 - i386, ia64, x86_64 Red Hat Enterprise Linux WS version 4 - i386, ia64, x86_64

3. Problem description:

The Common UNIX Printing System provides a portable printing layer for UNIX(R) operating systems.

During a source code audit, Chris Evans and others discovered a number of integer overflow bugs that affected all versions of Xpdf, which also affects CUPS due to a shared codebase. An attacker could construct a carefully crafted PDF file that could cause CUPS to crash or possibly execute arbitrary code when opened. This issue was assigned the name CAN-2004-0888 by The Common Vulnerabilities and Exposures project (cve.mitre.org). Red Hat Enterprise Linux 4 contained a fix for this issue, but it was found to be incomplete and left 64-bit architectures vulnerable. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2005-0206 to this issue.

A buffer overflow flaw was found in the Gfx::doImage function of Xpdf which also affects the CUPS pdftops filter due to a shared codebase. An attacker who has the ability to send a malicious PDF file to a printer could possibly execute arbitrary code as the "lp" user. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-1125 to this issue.

A buffer overflow flaw was found in the ParseCommand function in the hpgltops program. An attacker who has the ability to send a malicious HPGL file to a printer could possibly execute arbitrary code as the "lp" user. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-1267 to this issue.

A buffer overflow flaw was found in the Decrypt::makeFileKey2 function of Xpdf which also affects the CUPS pdftops filter due to a shared codebase. An attacker who has the ability to send a malicious PDF file to a printer could possibly execute arbitrary code as the "lp" user. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2005-0064 to this issue.

The lppasswd utility was found to ignore write errors when modifying the CUPS passwd file. A local user who is able to fill the associated file system could corrupt the CUPS password file or prevent future uses of lppasswd. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the names CAN-2004-1268 and CAN-2004-1269 to these issues.

The lppasswd utility was found to not verify that the passwd.new file is different from STDERR, which could allow local users to control output to passwd.new via certain user input that triggers an error message. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2004-1270 to this issue.

All users of cups should upgrade to these updated packages, which contain backported patches to resolve these issues.

4. Solution:

Before applying this update, make sure that all previously-released errata relevant to your system have been applied. Use Red Hat Network to download and update your packages. To launch the Red Hat Update Agent, use the following command:

up2date

For information on how to install packages manually, refer to the following Web page for the System Administration or Customization guide specific to your system:

http://www.redhat.com/docs/manuals/enterprise/

5. Bug IDs fixed (http://bugzilla.redhat.com/):

144191 - CAN-2004-1267 Bernstein cups issues (CAN-2004-1268 CAN-2004-1269 CAN-2004-1270) 144194 - CAN-2004-1125 xpdf buffer overflow 145088 - CAN-2005-0064 xpdf buffer overflow 147480 - CAN-2004-0888 xpdf issues affect cups (CAN-2005-0206)