The recent LIBPNG vulnerability can be exploited by sending HTML e-mail
containing an embedded malicious PNG image referenced locally using cid:
as well, if the recipient of the e-mail is using a vulnerable mail
client. See
Chris Evans' security advisory
http://scary.beasts.org/security/CESA-2004-001.txt
Therefore this issue is somewhat serious, and deserves more attention.
Mail clients need to block automatic display of all images, not just
those referenced by external URL inside an img tag. It is a lot of work
to locate vulnerable binary code, notify vendors of vulnerable or flawed
products and teach them this remedial basic security principle. I am
looking for volunteers who are interested in helping out with this effort.
Does anyone have a list of closed-source products known to contain
LIBPNG or code derived from it that is believed vulnerable?
Most Secure Regards,
Jason Coombs
Director of Forensic Services
PivX Solutions, Inc.
Jcoombs@PivX.com
-----Original Message-----
From: "CHRIS GRABENSTEIN" <CGRABENSTEIN@lfcc.edu>
Date: Mon, 23 Aug 2004 15:20:39
To:<security-basics@securityfocus.com>
Subject: RE: Images being pulled in Outlook 2003 even though don't
download pictures is set?
The reference after cid: refers to an image embedded in the email itself.
The image arrives as part of the email rather than being pulled from a
remote
server.
-----Original Message-----
From: Spencer, Mark [mailto:mspencer@evidentdata.com]
Sent: Sunday, August 22, 2004 12:36 PM
To: security-basics@securityfocus.com
Subject: Images being pulled in Outlook 2003 even though don't download
pictures is set?
I've been getting lots of spam with images being displayed, even though my
Outlook 2003 is set to not download pictures automatically. Here's what I
think is the relevant code (minus < and >):
DIV align=center
FONT face=Arial size=2
IMG src="cid:kfhyepds_bfjhwcxn_dkiaarqo";
/FONT
/DIV
/BODY
/HTML
Any advice on how to deal with this? How does that "cid: .." translate into
a legitimate IP address from which to pull an image?
Thanks!
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