The Exploit Post

Cisco has warned customers about an unpatched zero-day vulnerability in Cisco AsyncOS that is already being actively exploited in attacks targeting Secure Email Gateway (SEG) and Secure Email and Web Manager (SEWM) devices. The vulnerability, assigned the identifier CVE-2025-20393, affects only Cisco SEG and Cisco SEWM devices with non-standard configurations.

Cisco has warned customers about an unpatched zero-day vulnerability in Cisco AsyncOS that is already being actively exploited in attacks targeting Secure Email Gateway (SEG) and Secure Email and Web Manager (SEWM) devices. The vulnerability, assigned the identifier CVE-2025-20393, affects only Cisco SEG and Cisco SEWM devices with non-standard configurations.