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[Opendnssec-user] Re: Possible security issue in opendnssec due to misuse of the libcurl API


Ondřej Surý ondrej at debian.org
Mon Nov 26 10:40:31 GMT 2012


Hi,


eppclient from the opendnssec sources is not built and distributed as
a part of Debian binary packages.

However I am relaying your message to the upstream.

Ondrej.

On Sun, Nov 25, 2012 at 4:20 PM, Alessandro Ghedini <ghedo 
at debian.org> wrote: > Hi, > > I
recently discovered that opendnssec is using the libcurl API in a way
that may > not be what the original author intended. In
particular I'm referring to the > fact that the
CURLOPT_SSL_VERIFYHOST option is treated as it was a boolean value
> while in fact it isn't (it may take three different
values): > >  curl_easy_setopt(curl,
CURLOPT_SSL_VERIFYPEER, 1L); >  curl_easy_setopt(curl,
CURLOPT_SSL_VERIFYHOST, 1L); > > (from the file
plugins/eppclient/src/epp.c) > > Setting the value
to "1" does not enable the host checks (well, not all of
them) > and this may lead to security issues. The correct
value to enable all the > security checks is "2".
> > From the libcurl documentation: >
>> When CURLOPT_SSL_VERIFYHOST is 2, that certificate
must indicate that the >> server is the server to which
you meant to connect, or the connection fails. >>
>> Curl considers the server the intended one when the
Common Name field or a >> Subject Alternate Name field in
the certificate matches the host name in the >> URL to
which you told Curl to connect. >> >> When
the value is 1, the certificate must contain a Common Name field, but
it >> doesn't matter what name it says. (This is not
ordinarily a useful setting). >> >> When the
value is 0, the connection succeeds regardless of the names in the
>> certificate. > > After discussing
this with the security team, it was decided that it would be
> best if this was fixed before the Wheezy release.
> > Note that this should be fixed anyway, since
as of curl v7.28.1 (which will soon > be uploaded to
experimental) the value "1" is not a valid value anymore and
> libcurl will return an error. > > A
possible fix should be discussed with the opendnssec upstream first.
> > Cheers > > -- >
perl -E '$_=q;$/= @{[@_]};and s;\S+;<inidehG
ordnasselA>;eg;say~~reverse' 


-- Ondřej Surý <ondrej 
at sury.org> 

 
 
 

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