Fortinet is warning customers that attackers are exploiting a zero-day vulnerability (CVE-2026-104286) in FortiMail, its email security gateway. Fortinet says the flaw has been reported to be exploited in the wild, and urges customers to apply the workaround it shared until fixes are available.
Critical FortiMail zero-day exploited in the wild (CVE-2026-104286)
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