Twitter's Chief Information Security Officer (CISO) Lea Kissner announced that she is leaving the company. Calling it a "hard decision", Kissner tweeted, "I'm so proud of the privacy, security, and IT teams and the work we've done." Kissner, who joined Twitter last year, was promoted to CISO in January 2022 following the departure of security head Peiter "Mudge" Zatko.