Full Disclosure mailing list archives

Re: email attack vector just got wider


From: Micheal Espinola Jr <michealespinola () gmail com>
Date: Tue, 26 Apr 2005 12:56:23 -0400

an update:
 My latest finding is that Adobe PDF's with embedded attachments can be 
bundled and distributed as a Secure Electronic Envelope (eEnvelope). 
eEnvelopes are designed to protect documents in transit with the use of 
encryption.
 Password protected .ZIP's are typically addressed at the SMTP gateway by AV 
software with the option to strip or reject compressed file attachments that 
are not readily scan-able (due to the password protection, etc).
 Although Adobe recommends enabling scanning all file types in order to scan 
a PDF (and ass/u/me'ing its embedded contents as well), an AV scanner is not 
currently going to be able to scan this encrypted content until the content 
has been rendered/unencrypted at the desktop.
 While many AV vendors have factored certain compressed archive standards 
into their products, I have seen no indication that this is being addressed 
for this relatively new and already widely deployed product.
 Call me a worry-wort, but I foresee this is the next "in" for malware 
distribution.


On 4/25/05, Micheal Espinola Jr <michealespinola () gmail com> wrote: 

Perhaps not "just". My apologies for those that are aware of this, but it 
seems Adobe 6 also had this capability - although many people have been 
unaware of this. I recently upgrade from 5 to 7, so I missed this potential 
issue from the get-go. 
 Someone pointed out to me that Symantec does have a bulletin stating that 
by setting your AV to "scan all files" you can detect a virus inside a file 
embedded into a PDF.
 Unfortunately, this does not address the blocking of certain attachments 
outright.

 On 4/25/05, Micheal Espinola Jr <michealespinola () gmail com> wrote: 

It seems most people I know haven't noticed that the new version of 
Adobe Acrobat (7) now allows for embedded/attached documents.
 Since PDF's have generally been considered a safe document format and 
are typically not blocked by content/attachment scanners, this now opens an 
email-based attack vector that anti-virus providers [to the best of my 
knowledge] are not currently addressing. 
 Many thanks to Adobe for creating another issue for us to deal with, 
and especially for not having the forethought to coordinate with anti-virus 
vendors to prepare for assuredly future exploitation of the technology. 

-- 
ME2

my home: <http://www.santeriasys.net/>
my photos: < http://mespinola.blogspot.com/> 




-- 
ME2

my home: <http://www.santeriasys.net/>
my photos: < http://mespinola.blogspot.com/> 




-- 
ME2

my home: <http://www.santeriasys.net/>
my photos: <http://mespinola.blogspot.com/>
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