Microsoft Purview Information Protection uses cipher block chaining mode for encrypted content by default.

Originally posted by Microsoft May 31, 2023 Uncategorized 0 Comments

Today, when protecting content Microsoft Information Protection uses AES in electronic codebook (ECB) mode to encrypt Office files and emails. Starting in July, M365 Apps, Exchange Online, and SharePoint Online will begin to use cipher block chaining (CBC) mode by default.

Product	Word
Release phase	Semi-Annual Enterprise Channel (Preview)
Release date	July CY2023
Platform	Desktop
Cloud Instance	DoD, GCC, Worldwide (Standard Multi-Tenant), GCC High
Created	2023-05-31
Roadmap ID	117576
Roadmap Link	https://www.microsoft.com/microsoft-365/roadmap?featureid=117576