OpenBMC and https Vulnerable issue.

[James Feist]

On 11/6/19 2:38 PM, Bruce Mitchell wrote:
> 
> 
>> -----Original Message-----
>> From: openbmc [mailto:openbmc-
>> bounces+bruce_mitchell=phoenix.com at lists.ozlabs.org] On Behalf Of Bruce
>> Mitchell
>> Sent: Wednesday, November 6, 2019 14:19
>> To: James Feist; OpenBMC Maillist
>> Subject: RE: OpenBMC and https Vulnerable issue.
>>
>>
>>
>>> -----Original Message-----
>>> From: openbmc [mailto:openbmc-
>>> bounces+bruce_mitchell=phoenix.com at lists.ozlabs.org] On Behalf Of
>>> James Feist
>>> Sent: Wednesday, November 6, 2019 13:52
>>> To: Bruce Mitchell; OpenBMC Maillist
>>> Subject: Re: OpenBMC and https Vulnerable issue.
>>>
>>> On 11/6/19 11:31 AM, Bruce Mitchell wrote:
>>>>   From my investigations on TLS there seems to be 2 issues that could be
>>> corrected with OpenBMC's https:
>>>>     1  Secure Client-Initiated Renegotiation     VULNERABLE (NOT ok), DoS
>>> threat
>>>
>>> This CVE is disputed https://www.cvedetails.com/cve/CVE-2011-1473/ due
>>> to CPU consumption issues that might make it easier to cause a DOS
>>> (which is arguably already not that difficult on a BMC). That being said
>>> the fix is a 1 liner, so I implemented it and it seems to work, but I
>>> need to see if there are any consequences.
>>>
>>> https://gerrit.openbmc-project.xyz/c/openbmc/bmcweb/+/26992
>>>
>>>
>>>
>>>>     2  LUCKY13 (CVE-2013-0169), experimental     potentially VULNERABLE,
>>> uses cipher block chaining (CBC) ciphers with TLS
>>>>        and xc023   ECDHE-ECDSA-AES128-SHA256         ECDH 521   AES         128
>>> TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
>>>
>>> Based on this https://wiki.crashtest-security.com/prevent-ssl-lucky13,
>>> we are using the recommended ciphers,
>>>
>> https://github.com/openbmc/bmcweb/blob/1f8c7b5d6a679a38b8226106031
>>> 0b876079d0f8b/include/ssl_key_handler.hpp#L330.
>>> And based on this comment from the maintainer of test ssl, no tool can
>>> determine this externally, and it's just a warning:
>>> https://github.com/drwetter/testssl.sh/issues/1011#issuecomment-
>>> 372953654.
>>> Do you have any suggestions on if there is anything to change for this one?
>>>
>>> Thanks
>>>
>>> -James
>>>
>>
>> Thanks James, I accept your assessment.
>>
>> -Bruce
>>
> 
> There are Mozilla Recommended configurations as well.
> https://wiki.mozilla.org/Security/Server_Side_TLS#Recommended_configurations
> 

I believe that's what was originally copied based on the variable name 
in ssl_key_handler.hpp.

> - Bruce
> 
>>>
>>>>
>>>> Present standard of practice seems to be to not allow Secure Client-
>>> Initiated Renegotiation and to not allow CBC ciphers.
>>>>
>>>> Is this your understanding as well?
>>>>
>>>> Thank you!
>>>>
>