Critical Cisco Secure Email Gateway Vulnerability Exploited in the Wild (CVE-2026-76461)

Cisco Secure Email Gateway processes inbound and outbound email traffic as part of normal operation. According to Cisco[1], exploitation does not require authentication or access to an administrative interface. An attacker can reportedly trigger the vulnerability through malicious email content processed by the gateway. Cisco has stated that it became aware of active exploitation in September 2026, indicating that the vulnerability was exploited prior to public disclosure.…