Researcher Josip Franjković documented multiple race condition vulnerabilities discovered in Facebook, DigitalOcean, and LastPass that allowed attackers to bypass single-action restrictions by sending concurrent requests—including inflating page reviews, creating multiple usernames, and redeeming promo codes multiple times. All bugs were subsequently fixed and disclosed through responsible disclosure timelines.
Site-wide CSRF vulnerability discovered on Messenger.com where CSRF token (fb_dtsg) validation was completely missing on multiple endpoints, allowing attackers to perform unauthorized actions like changing settings and removing users from group threads. The vulnerability affected all POST requests regardless of whether the token was modified, removed, or omitted entirely.