Dailydave mailing list archives
Flashy.
From: Dave Aitel <dave () immunityinc com>
Date: Thu, 13 Nov 2008 18:19:27 -0500
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Some web sites are secure. It's annoying, but it's the way it is with modern libraries and web application packs. However, even on web sites that are fundamentally strong, sometimes the random third party things they use interacts with a web browser in a way they can't hope to inspect. Flash is a key example. Although it's not mentioned anywhere clearly that I can see, IE and Firefox treat SWF files somewhat differently. If you browse to http://www.example.com/bob.swf?a=b in IE, it will render it. If you do the same in Firefox, it will download the swf file. People make oblique comments about IFrames being able to force Firefox to behave like IE, but I don't think it works. IE behaving like this makes some poorly coded Flash (ActionScript 2) movies vulnerable to cross site scripting. Lots of web sites provide Flash movies as "Demos" of their product. To the web developer, these are just images they serve up. To the hacker, they're full blown applications to decompile (thanks flare!) and attack. SWFIntruder, while very good work, is not a magic button to get your XSS found and fixed, fortunately for those of us in the assessment business this week. :> So even when your website itself is completely secure, the interaction between your website and the browser is often not, which is a funny thing. This is one of the things that was discussed during the panel (we tried to make it fun!) in Chicago last week but it's good to see it in practice. - -dave -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFJHLX+tehAhL0gheoRAp+fAJ9OFbOKpJsTAzPX13vTP520D5jMzQCfbVaS 2v85tvVz44HFgJE3PTIV3H8= =H1Ly -----END PGP SIGNATURE----- _______________________________________________ Dailydave mailing list Dailydave () lists immunitysec com http://lists.immunitysec.com/mailman/listinfo/dailydave
Current thread:
- Flashy. Dave Aitel (Nov 13)
