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CA-2001-32 Buffer Overflow in HP-UX Line Printer Daemon


CERT Advisory CA-2001-32 Buffer Overflow in HP-UX Line Printer Daemon

Original release date: November 21, 2001
Last revised: --
Source: CERT/CC

A complete revision history can be found at the end of this file.

Systems Affected

HP9000 Servers running the following releases:

* HP-UX Version 10.01
* HP-UX Version 10.10
* HP-UX Version 10.20
* HP-UX Version 11.00
* HP-UX Version 11.11


The HP-UX line printer daemon (rlpdaemon) enables various clients
to share printers over a network. A remotely exploitable buffer
overflow vulnerability exists in the rlpdaemon.

I. Description

By sending a specially crafted print request to an HP-UX host
running the rlpdaemon, a local or remote attacker can trigger the
buffer overflow. Intruders may find this vulnerability attractive
to exploit because the line printer daemon is enabled by default to
provide printing services. Additionally, no previous knowledge of
or access to the vulnerable system is required for exploitation.

Internet Security Systems (ISS) and Hewlett-Packard Company have
issued the following announcements, respectively:

Remote Logic Flaw Vulnerability in HP-UX Line Printer Daemon

Hewlett-Packard Company Security Bulletin #0176

This vulnerability has been assigned the identifier CAN-2001-0817
by the Common Vulnerabilities and Exposures (CVE) group:

For the latest and most detailed information about this
vulnerability, please see VU#638011.

II. Impact

An attacker can execute arbitrary code on the target system with
the privileges of the line printer daemon, typically superuser.

III. Solution

Install a patch from HP. More information is available in Appendix

Restrict access to the lpd service

As a general practice, we recommend disabling all services that are
not explicitly required. You may wish to disable the line printer
daemon until a patch can be applied. If you cannot disable the
service, you can limit your exposure to these vulnerabilities by
using a router or firewall to restrict access to port 515/TCP
(printer). Note that this does not protect you against attackers
from within your network.

Appendix A. - Vendor Information

This appendix contains information provided by vendors for this
advisory. When vendors report new information to the CERT/CC, we
update this section and note the changes in our revision
history. If a particular vendor is not listed below, we have not
received their comments.

Hewlett-Packard Company

Please see Hewlett-Packard Company Security Bulletin #0176.

Appendix B. - References


This vulnerability was discovered and researched by Mark Dowd and
Kris Hunt of Internet Security Systems (ISS). The CERT/CC thanks
ISS for the information contained in their advisory.

Author: Ian A. Finlay.

This document is available from:

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Revision History

November 21, 2001: initial release

Version: PGP 6.5.8


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