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 electronically. It may not be edited in any way without the express written consent of iDEFENSE. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please email customerservice@xxxxxxxxxxxx for permission. 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.
