Twitter’s former top security official has alleged that company executives endangered national security through “egregious deficiencies” in privacy and security and systematically misled users, members of its board, investors, and government officials about those vulnerabilities.

The former official, Peiter “Mudge” Zatko, is a famous hacker and one of the nation’s top cybersecurity experts. He served as Twitter’s security lead from Nov. 2020 to Jan. 2022, when he was fired by CEO Parag Agrawal after Zatko began documenting what he says were repeated security violations, and as he worked with the company’s compliance officer on a formal investigation based on his claims. Zatko submitted his disclosures to U.S. regulatory agenc…