Critical FortiMail Zero-Day Flaw Actively Exploited in Attacks

CISA has added a critical Fortinet FortiMail security flaw to its Known Exploited Vulnerabilities catalog following active exploitation in the wild. Tracked as CVE-2026-104286 with a maximum CVSS score of 9.8, the vulnerability allows unauthenticated attackers to perform arbitrary file writes on vulnerable systems. Administrators should apply available patches immediately to mitigate potential system compromise.