Hi Nick,

any link to the source code?

Regards,
Yann.


On Fri, Sep 26, 2014 at 4:41 PM, Nick Kew <[email protected]> wrote:
> I've revisited mod_taint this morning, and made some updates:
> a bugfix, a new option to apply an untainting rule to all headers.
> But topically, a canned configuration option to protect
> against shell-shock patterns:
>
>   LoadModule modules/mod_taint.so
>   Untaint shellshock
>
> Untaint works in a directory context, so can be
> selectively enabled for potentially-vulnerable apps
> such as those involving CGI, SSI, ExtFilter,
> or (other) scripts.
>
> This goes through all Request headers, any PATH_INFO
> and QUERY_STRING, and (just to be paranoid) any
> other subprocess environment variables.  It untaints
> them against a regexp that checks for "()" at the
> beginning of a variable, and returns an HTTP 400 error
> (Bad Request) if found.
>
> Feedback welcome, indeed solicited.  I believe this
> is a simple but sensible approach to protecting
> potentially-vulnerable systems, but I'm open to
> contrary views.  The exact details, including the
> shellshock regexp itself, could probably use some
> refinement.  And of course, bug reports!
>
> Builds and runs with httpd 2.2 and 2.4.  Very limited
> testing verifies that it catches a shellshock attack
> in a request header.
>
> http://people.apache.org/~niq/mod_taint.html
>
> Note: cross-posting, with followup-to set to dev@.
> If you're following up to report a critical bug,
> adding users@ will ensure widest exposure!
>
> --
> Nick Kew

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