Public Vulnerability Reports

ELOG Format String and Multiple Buffer Overflow Vulnerabilities

12.29.02

BACKGROUND

ELOG is an electronic logbook package. ELOG can be installed on Windows and Unix systems as a standalone application or as part of the Midas package, also developed by the same author. Detailed information about ELOG is available at http://midas.psi.ch/elog/.

DESCRIPTION

Numerous remotely exploitable vulnerabilities have been discovered in Stefan Ritt's Electronic Logbook (ELOG).

ELOG is an electronic logbook available for Linux and Microsoft Windows operating systems. Three separate classes of vulnerabilities have been discovered in ELOG: a remotely exploitable format-string vulnerability, many remotely exploitable buffer-overflow conditions, and the mismanagement of sensitive data by the web interface.

Format String Vulnerability

Line 10,754 in the file elogd.c contains the following vulnerable snippet of code:

printf(net_buffer);

Buffer Overflows

The file elogd.c contains many vulnerable snippets of code that create remotely exploitable buffer overflow conditions.

Insecure Handling of Sensitive Data

Several web pages created by the ELOG daemon store passwords in plaintext within hidden form fields.

ANALYSIS

Any remote user with access to an affected server could exploit any of the above-described vulnerabilities. Successful exploitation would provide the remote attacker with access to the target server under the privileges of the user that spawned the ELOG daemon. The attacker could then utilize local privilege escalation attacks to further compromise the system.

iDEFENSE has proof of concept exploit code demonstrating the impact of this vulnerability.

DETECTION

iDEFENSE has verified the existence of these vulnerabilities in the latest versions of ELOG, versions 2.2.2 and 2.2.3.

WORKAROUND

Restrict access to the ELOG daemon to only trusted users. Use a filtering proxy to help mitigate attacks.

VENDOR RESPONSE

Reportedly, this issue was fixed in version 2.2.4 of ELOG

CVE INFORMATION

A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not been assigned to this issue.

DISCLOSURE TIMELINE

11/30/2002   Exploit acquired by iDEFENSE
12/03/2002     Initial vendor notification
12/21/2002   iDEFENSE Clients notified
12/29/2002   Public Disclosure

CREDIT

zilli0n is credited with this discovery.

Get paid for vulnerability research
http://www.idefense.com/poi/teams/vcp.jsp

LEGAL NOTICES

Copyright © 2004 Verisign, 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@idefense.com 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.