This is in from Authorize.net. The latest updaters are compatible with the new SHA based signature keys so we recommend you update as soon as possible.

quote:

---

Today we’re announcing final phase 2 dates when the gateway will stop populating the MD5 hash value.

Phase 1 Complete
Phase 2 - Stop sending the MD5 Hash data element in the API response. To continue verifying via hash, this will require applications to support the SHA-512 hash via signature key.
Sandbox will be updated on March 7, 2019 to stop populating the MD5 Hash value, the field will still be present but empty.
Production will be updated on March 14, 2019 to stop populating the MD5 Hash value, the field will still be present but empty.

---

Vince

Click Here for Shopping Cart Software
Click Here to sign up for our newsletter
Click Here for the latest updater