- From: Ian Hickson via cvs-syncmail <cvsmail@w3.org>
- Date: Fri, 16 Dec 2011 00:32:45 +0000
- To: public-html-commits@w3.org
Update of /sources/public/html5/spec In directory hutz:/tmp/cvs-serv11505 Modified Files: Overview.html Log Message: Mention some XSS risks explicitly. (whatwg r6875) Index: Overview.html =================================================================== RCS file: /sources/public/html5/spec/Overview.html,v retrieving revision 1.5474 retrieving revision 1.5475 diff -u -d -r1.5474 -r1.5475 --- Overview.html 15 Dec 2011 00:44:25 -0000 1.5474 +++ Overview.html 16 Dec 2011 00:32:40 -0000 1.5475 @@ -320,7 +320,7 @@ <h1>HTML5</h1> <h2 class="no-num no-toc" id="a-vocabulary-and-associated-apis-for-html-and-xhtml">A vocabulary and associated APIs for HTML and XHTML</h2> - <h2 class="no-num no-toc" id="editor-s-draft-15-december-2011">Editor's Draft 15 December 2011</h2> + <h2 class="no-num no-toc" id="editor-s-draft-16-december-2011">Editor's Draft 16 December 2011</h2> <dl><dt>Latest Published Version:</dt> <dd><a href="http://www.w3.org/TR/html5/">http://www.w3.org/TR/html5/</a></dd> <dt>Latest Editor's Draft:</dt> @@ -467,7 +467,7 @@ Group</a> is the W3C working group responsible for this specification's progress along the W3C Recommendation track. - This specification is the 15 December 2011 Editor's Draft. + This specification is the 16 December 2011 Editor's Draft. </p><!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><p>Work on this specification is also done at the <a href="http://www.whatwg.org/">WHATWG</a>. The W3C HTML working group actively pursues convergence with the WHATWG, as required by the <a href="http://www.w3.org/2007/03/HTML-WG-charter">W3C HTML working group charter</a>.</p><!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><p>This document was produced by a group operating under the <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 @@ -1789,7 +1789,27 @@ </div> - </dd> + <p>There are many constructs that can be used to try to trick a + site into executing code. Here are some that authors are + encouraged to consider when writing whitelist filters:</p> + + <ul><li>When allowing harmless-seeming elements like + <code><a href="#the-img-element">img</a></code>, it is important to whitelist any provided + attributes as well. If one allowed all attributes then an + attacker could, for instance, use the <code title="handler-onload"><a href="#handler-onload">onload</a></code> attribute to run arbitrary + script.</li> + + <li>When allowing URLs to be provided (e.g. for links), the + scheme of each URL also needs to be explicitly whitelisted, as + there are many schemes that can be abused. The most prominent + example is "<code agents="" but="" can="" have="" historically="" implement="" implemented="" indeed="" others="" title="javascript:</code>" user=""> + + <li>Allowing a <code><a href="#the-base-element">base</a></code> element to be inserted means any + <code><a href="#the-script-element">script</a></code> elements in the page with relative links can + be hijacked, and similarly that any form submissions can get + redirected to a hostile site.</li> + + </code></ul></dd> <dt>Cross-site request forgery (CSRF)</dt>
Received on Friday, 16 December 2011 00:32:52 UTC