RE: [webappsec] Call for Consensus: CSP 1.1 to FPWD

Dear Brad,

Using a <meta> element for the CSP is problematic and I recommend it be moved to an attribute on the <html> element.  Further I recommend that injection of such an attribute be ignored so that only the static markup can have any effect.

Using a <meta> element opens a range of complex issues, such as synchronizing the start of a CSP with ongoing asynchronous page load actions and the retrospective application of restrictions to running JS contexts.  To make it reliable might require the introduction of a dependency notation and this may not be worth the effort.

The security work of PUA CG requires a static mechanism for specifying the CSP to avoid the initiation of the CSP being used to leak information and a <html> attribute will likely be used to avoid having to reading ahead for a CSP <meta> element.   This appears much easier to implement and would be a subset of the proposed CSP 1.1 <meta> element and perhaps it would be adequate and better suit browser vendors anyway.

cheers
Fred

From: bhill@paypal-inc.com
To: public-webappsec@w3.org
Date: Tue, 27 Nov 2012 22:01:20 +0000
Subject: [webappsec] Call for Consensus: CSP 1.1 to FPWD

Received on Tuesday, 27 November 2012 23:46:21 UTC