[Full-disclosure] noise about full-width encoding bypass?

Brian Eaton eaton.lists at gmail.com
Mon May 21 16:33:08 BST 2007


On 5/21/07, Łukasz Pilorz <lukasz at pilorz.net> wrote:
> I think this encoding bypass may have some impact on applications
> which convert data from Unicode/UTF to other encodings. A naive
> example:
> http://lukasz.pilorz.net/testy/full_width_utf/index.phps
>
> But I don't suggest this was the main problem, I have probably missed
> something too.

Your POC works for me, the PHP iconv code converts the UTF-8 byte
sequence 0xef  0xbc 0x9C to ASCII '<'.  Looks like PHP applications
may be at risk.

The java CharsetDecoder class does not.  (I don't think this will be
JRE specific, but I tested the IBM JRE...).

The perl Encode module does not.

Anybody have an IIS server handy, to test out how .NET handles this?

Regards,
Brian


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