Authorize.net Direct Post transaction key update (MD5 to SHA-512)

[wejobes]

I just got an email from authorize.net stating that at the end of January 2019 they will no longer be using MD5 for their transHash key, but will be using SHA-512.  They contacted us, because our client uses Authorize.net Direct Post payment method in Magento 1.  Does anyone know if Magento is working on an update for this module?  The Authorize.net Direct Post payment method is defined in a core module (Mage_Authorizenet), and before I start overriding to update, I would like to know if there is an update coming from Magento for this module.  I know we are getting to the end of support for Magento 1, due to Magento 2, but these things need to stay up to date until this time comes.  

If anyone knows if Magento is working on an update for this or who has already made an update to this that they can share with me, that would be great.  If not, I will attempt to share any changes I make for others to use.

[Shimon2]

We are using Magento 2 and we received the same email.  I only see an MD5 key in the Configuration>Payment Methods>Other Payment Methods>Authorize.net Direct Post settings.

Do we need a new extension?  What is the path?  End of January is only 2 weeks away.

Thanks

[dbrooke1007]

I had posted about this last week:

https://community.magento.com/t5/Magento-2-x-Technical-Issues/Authorize-Net-core-needs-changes/m-p/1...

I too would like to know if anyone is working on a fix. In lieu of an official fix, I'd be interested in what you do to fix it. I think the "fix" could be as easy as changing the code to not *require* the MD5 Value.

Though the backend does not say it is required, Magento 2 throws an error upon payment if it's not filled thus disabling checkout.

[dbrooke1007]

I'm going to point everyone in these multiple alike threads to one thread, here:

The only reason being that this guy has the best subject description.