Apple's macOS Screen Sharing Flaw CVE-2026-65400 Is Under Active Exploitation

Dutch officials warned that a high-severity macOS vulnerability, CVE-2026-65400, is being actively exploited on systems with port 5900 exposed to the internet. Apple patched the screen sharing flaw, which has a 7.1 severity rating, for macOS Tahoe, Sequoia, and Sonoma. The author's always-on Mac Mini was compromised, and he used Claude to identify the intrusion and wipe the machine.