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Critical Vulnerability In Adobe Reader
An anonymous reader writes "Core Security Technologies issued an advisory disclosing a vulnerability that could affect millions using Adobe's Reader PDF file viewing software. Engineers from CoreLabs determined that Adobe Reader could be exploited to gain access to vulnerable systems via the use of a specially crafted PDF file with malicious JavaScript content. Successful exploitation of the vulnerability requires that users open a maliciously crafted PDF file, thereby allowing attackers to gain access to vulnerable systems and assume the privileges of a user running Acrobat Reader."
That might work on some or most files, but there still is no replacement for Acrobat.
Adobe Reader is very slow to load and freezes your browser. Yes, it's very difficult to tell.
Does Adobe Reader come with a "safe mode" with just plain old PDF enabled?
If not, it should.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
...with the privileges of a user running the Adobe Reader application.
Which strongly implies that those affected will be Windows users with Administrator access.
It seems fair to worry even if you aren't running as admin. If a trojan PDF can run arbitrary code with privileges of the user running Adobe Reader, that's still enough to screw with that user's documents even if the user isn't an admin.
Perhaps, but you can have multiple PDF readers installed. And in terms of security, it's usually best to use the simplest application that will work.
So basically you could use FoxIt or Sumatra PDF to open most PDFs. And then for the rare one that uses some advanced stuff, you can fire up Acrobat. The fact is that most of the stuff that Acrobat supports that other PDF readers don't involves some kind of scripting. And really you shouldn't be running any scripts (even those that are, in principle, sandboxed) unless you have reason to trust them.
So a sensible strategy would seem to be that you open 99% of PDFs with a simpler reader, and only use Acrobat on the few that really need it, and only if the source of the PDF is trustworthy in your estimation.
(Yeah, I know... it's a bit of a pain to have multiple programs that do the same thing. In principle you "shouldn't have to" in the sense that your PDF reader should be secure. But in reality it seems like a reasonable precaution.)
...begs the question "Why Does Adobe Reader Need Javascript"??
Coder's Stone: The programming language quick ref for iPad
This is exactly what I do in Mac OS X. Virtually always, I just open the PDF with Preview.app (part of the basic OS distribution). On the rare occasion that it won't open or is a form or something, I'll right-click>open with>Acrobat.app. Not much of a pain.
I think it makes good sense to have a different app depending on what you need done. For instance, reading articles in PDF in Preview or Acrobat is a pain, and I'll use Skim.app for those.
The real solution is to open 100% of PDFs in a simpler reader, and refuse to tolerate PDFs that require scripting.
Really, there's no good reason for a document viewer to have the bloat of Acrobat, and we shouldn't encourage Adobe by doing what they want.
Adobe is one of the best when it comes to cross-platform compatibility and the hole is based on Javascript...
And yes, I did RTFA.
No javascript in pdf is an excellent solution. It's a DOCUMENT, not a video game or word processor or anything else. You don't get javascript on a paper printout; you don't need javascript in the electronic version of a paper printout.
Few people disable javascript in their browsers.
I do. Most javascript in web pages is useless and needless and a waste of computer cycles. If you want to calculate something, do it on YOUR SEVER and send me the result.
It's a crutch used by poor web designers to add glitz to content-less pages.
I caught a major cell-phone company using javascript to provide log-in security for their account access web pages. Since I had javascript turned off, I had access to anyone's account I wanted. I told them what I was doing and they didn't believe it, until I started telling the account manager I was talking to what his minute balance and last payment was. THEN he got interested.
Much better that pdf authors spend the time properly identifying their documents with title and author information. I have US Government produced pdfs where the "title" of the document is "Microsoft preview -- C:\some\file\name\that\is\meaningless.doc" and the author is even stupider. Leave out the fancy crap until you can properly identify your documents, ok?
You need evidence that javascript on web pages is useless? Try Yahoo. I go to my Yahoo mail page and a big, time-wasting page tells me that I have javascript turned off, click here for the OLD version of mail -- which is exactly where I was trying to get to in the first place, damn it!
And get off my lawn...
When I install a new piece of software, the first place I go is to the preferences panel to see if there are any stupid/broken settings that need to be fixed (or, too often, fixed again after an upgrade). I can't remember which version it originally showed up in, but when I saw the checkbox for JavaScript in Acrobat Reader, my jaw hit the floor.
"Are you people fscking morons? Did you learn nothing from the exploits and problems caused by JavaScript in Web browsers? Hell, forget Web browsers; Microsoft Word became a virus/trojan platform because the Special-Needs Children who apparently design all their software thought it would be tEh k00l to embed macros in what is fundamentally a static document."
Every time some would-be clever person adds a macro language or other executable logic to a document format, the result is "unexpected" worms, viruses, and security breaches. Every God-damned time.
This is not an honest mistake. This is negligent engineering, and someone needs to lose a lot of money over it before the lesson sinks in.
Schwab
Editor, A1-AAA AmeriCaptions