If you want to dive deep into guaranteed end-to-end encryption and how green checkmarks protect against compromised servers ("MITM attacks"), the "Cryptographic Analysis of Delta Chat" from Applied Cryptography researchers at ETH Zuerich has been published at https://eprint.iacr.org/2024/918.pdf -- earlier this year we had blogged from our side how we addressed all findings https://delta.chat/en/2024-03-25-crypto-analysis-securejoin

#securejoin #deltachat

Delta Chat: Hardening Guaranteed End-to-End encryption based on a security analysis from ETH researchers

We released guaranteed end-to-end encryption in November 2023 and were in for a pleasant surprise three months later. The Applied Cryptography Group at ETH Zurich handed us a cryptographic security...

^delta.chat