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Re: [Json] Security considerations

Carsten Bormann <cabo@tzi.org> Sun, 06 October 2013 08:12 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Sun, 06 Oct 2013 10:12:21 +0200
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To: Tim Bray <tbray@textuality.com>
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Subject: Re: [Json] Security considerations
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On Oct 6, 2013, at 08:10, Tim Bray <tbray@textuality.com> wrote:

> It dawns on me that the #1 security consideration every web programmer learns, when using JSON, is “You could parse it with eval() but DON’T DO THAT”. So should we include that in the -bis Security Considerations section?

Yes!

Phrased this way, that would be a security consideration specific to JavaScript.  It may be worthwhile pointing out that there have been attack vectors*) in other environments as well that have tried some simple, incompletely checked syntactical conversion from JSON into their own (unsafe) literal notation and loaded/executed that.

Grüße, Carsten

*) say, CVE-2013-0269, CVE-2013-0333

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