Re: [CVE-2020-28018] Use-After-Free on Exim Question

[Qualys Security Advisory <qsa () qualys com>]

Hi,

On Tue, May 11, 2021 at 11:18:12PM +0200, null p0int3r wrote:
> In the advisory it is mentioned the use of the name=value pair, but reading
> the code I see just string based functions used for allocations.

One of the name=value parameters for MAIL FROM is special, because it
can allocate arbitrary (binary) characters (hint: we also used it to
exploit another vulnerability in the advisory)!

With best regards,

--
the Qualys Security Advisory team


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