[Full-Disclosure] iDEFENSE Security Advisory 04.05.04: Perl win32_stat Function Buffer Overflow Vulnerability

2004-04-05T00:00:00
ID SECURITYVULNS:DOC:6016
Type securityvulns
Reporter Securityvulns
Modified 2004-04-05T00:00:00

Description

Perl win32_stat Function Buffer Overflow Vulnerability

iDEFENSE Security Advisory 04.05.04 www.idefense.com/application/poi/display?id=93&type=vulnerabilities April 5, 2004

I. BACKGROUND

Perl is a popular programming language due to its text manipulation capabilities and rapid development cycle. It is open source, cross platform and used for mission critical projects in the public and private sector.

II. DESCRIPTION

Remote exploitation of a buffer overflow in the 'win32_stat' function of ActiveState's ActivePerl and Larry Wall's Perl could allow for the execution of arbitrary commands.

If the filename passed to the function ends with a backslash character, it is copied into a fixed length buffer. There is no check made on the length of the string before the copy, allowing an excessively long string to overwrite control information, allowing execution of arbitrary code.

The problem specifically exists within the win32 wrapper to the stat() routine and hence the Unix builds of Perl are not affected.

III. ANALYSIS

The 'win32_stat' function is a wrapper around the 'stat' function and the file test operators ('-r', '-w', '-e', '-d' etc) on Win32 based platforms.

If a web site contains a Perl script that uses any of these functions with user supplied pathnames, it may be possible to remotely execute commands.

IV. DETECTION

All versions of Perl for Win32 operating systems up to and including 5.8.3 are affected.

V. VENDOR RESPONSE

The fix will be incorporated into core Perl 5.8.4. Patches are currently available at the following locations:

Committed to the Perl 5.9.x development branch:

http://public.activestate.com/cgi-bin/perlbrowse?patch=22466

Integrated into Perl 5.8.x maintenance branch as part of:

http://public.activestate.com/cgi-bin/perlbrowse?patch=22552

VI. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the name CAN-2004-0377 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org), which standardizes names for security problems.

VII. DISCLOSURE TIMELINE

January 09, 2004 Vulnerability discovered by iDEFENSE February 25, 2004 Initial vendor contact February 26, 2004 iDEFENSE clients notified February 26, 2004 Vendor response April 05, 2004 Public disclosure

VIII. CREDIT

Greg MacManus (iDEFENSE Labs) is credited with this discovery.

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

IX. 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@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.


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