Bugtraq mailing list archives
RE: Buffer Overflow in ActivePerl ?
From: "Drew Copley" <dcopley () eeye com>
Date: Tue, 18 May 2004 15:23:16 -0700
-----Original Message----- From: noderat () hotmail com [mailto:noderat () hotmail com] Sent: Tuesday, May 18, 2004 9:11 PM To: bugtraq () securityfocus com Subject: Re: Buffer Overflow in ActivePerl ? In-Reply-To: <40AAB885.10935.31071242@localhost>Looks like full control of EIP...However, there is not likely to be a privilege escalationhere unlessperhaps a script processor on a web server can be cajoled into doingsomething with this?? (Not at all familiar with the innardsof Windowsweb servers and their relationship to their CGI, etc processors...)--Nick FitzGeraldComputer Virus Consulting Ltd.Ph/FAX: +64 3 3529854Unethical intruders don't always require "privilege escalation", executing code on another system is enough, depending on the goal. Networks where say developers are sharing source tree's and the like, placing a hostile piece of code in the central store will allow remote code execution on the developer nodes.
The beauty of holes in perl itself is the possibility that it could affect a widerange of perl scripts out there sleeping on people's webservers, though. I would guess, however, a function named "system" is not likely used by very many scripts and probably has some serious other issues. ... looking ... http://iis1.cps.unizar.es/Oreilly/perl/learn32/ch14_01.htm#ch14-23962 example given: system("dir >this_dir") && die "cannot create this_dir"; ... Yeah, so if you have control over the parameter of "system" call in perl on a webserver, you have complete access, anyway. People should look at the other functions in there. This is interesting as it may be that there are more easily accessible functions in there which may be exploitable. With an overflow attack, or similiar, you would bypass - likely - most mechanisms designed to filter out your typical injection attacks which generally rely on logical operators and the such -- not just too long of variables or otherwise improper but valid variables.
Other registers other than EIP can be written, depending on the version, however we need not rely on EIP to allow for a buffer overflow exploit, we don't "need" to overwrite any register in fact to execute code, only to cause a buffer overflow >;] cheers
Current thread:
- Buffer Overflow in ActivePerl ? Oliver () greyhat de (May 17)
- Re: Buffer Overflow in ActivePerl ? rich . sf (May 18)
- RE: [Full-Disclosure] Re: Buffer Overflow in ActivePerl ? Bill Royds (May 18)
- Re: Buffer Overflow in ActivePerl ? Josh Tolley (May 18)
- Re: Buffer Overflow in ActivePerl? Axel Beckert (May 18)
- Re: Buffer Overflow in ActivePerl ? Nick FitzGerald (May 18)
- <Possible follow-ups>
- Re: Buffer Overflow in ActivePerl ? noderat (May 18)
- RE: Buffer Overflow in ActivePerl ? Drew Copley (May 18)
- Re: Buffer Overflow in ActivePerl ? David Cantrell (May 19)
- Re: Buffer Overflow in ActivePerl ? David Ahmad (May 19)
- Re: Buffer Overflow in ActivePerl ? David Cantrell (May 19)
- Re: Buffer Overflow in ActivePerl ? rich . sf (May 18)