Hewlett Packard HP-UX ftpd Remote Buffer Overflow Vulnerability
iDEFENSE Security Advisory 12.21.04
www.idefense.com/application/poi/display?id=175&type=vulnerabilities
December 21, 2004
I. BACKGROUND
HP-UX FTP Daemon is a service included in HP-UX that implements the File
Transfer Protocol.
II. DESCRIPTION
Remote exploitation of a buffer overflow vulnerability in the file
transfer protocol (FTP) daemon included in multiple versions of Hewlett-
Packard Development Co.'s (HP) HP-UX allows attackers to gain remote
root access in certain configurations.
The problem specifically exists when the FTP daemon is configured via
/etc/inetd.conf to log debug information using -v switch. This is a not
a default configuration option. When parsing a long command request, an
exploitable stack overflow will occur. The overflow occurs before
authentication, thus eliminating the need for a local or anonymous FTP
account.
III. ANALYSIS
Exploitation of this vulnerability allows unauthenticated remote
attackers to execute arbitrary code under the privileges of the FTP
daemon server, usually root. The severity of this issue is mitigated by
the fact that in most production environments, administrators will not
be using the debug-logging feature of FTP daemon.
IV. DETECTION
iDEFENSE has confirmed the existence of this vulnerability in HP-UX
11.11i. It is suspected that previous versions are also vulnerable.
To determine if a specific configuration is vulnerable, check
/etc/inetd.conf for the ftpd line and see if the debug switch is
enabled:
grep 'ftpd' /etc/inetd.conf | grep -- -v
If the above command returns text, then the FTP daemon is running in
debug mode.
V. WORKAROUND
Do not use the -v flag in the FTP daemon entry line in /etc/inetd.conf.
If debug-logging is necessary, consider allowing only trusted hosts
access to the service using firewall rules or TCP wrappers.
VI. VENDOR RESPONSE
This vulnerability was addressed in the following patches:
HP-UX B.11.00: PHNE_29460
HP-UX B.11.04: PHNE_31034
HP-UX B.11.11: PHNE_29461
HP-UX B.11.22: PHNE_29462
VII. CVE INFORMATION
A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not
been assigned yet.
VIII. DISCLOSURE TIMELINE
12/02/2004 Initial vendor notification
12/03/2004 Initial vendor response
12/21/2004 Public disclosure
IX. CREDIT
iDEFENSE Labs is credited with this discovery.
Get paid for vulnerability research
http://www.idefense.com/poi/teams/vcp.jsp
X. LEGAL NOTICES
Copyright (c) 2004 iDEFENSE, Inc.
Permission is granted for the redistribution of this alert
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part of this alert in any other medium other than electronically, please
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Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct, indirect,
or consequential loss or damage arising from use of, or reliance on,
this information.
