100+ Cisco Secure Email Devices Exposed to Zero‑Day Exploited in the Wild

Cybersecuritynews •Guru Baran • December 21, 2025

Security researchers have identified at least 120 Cisco Secure Email Gateway and Cisco Secure Email and Web Manager devices vulnerable to a critical zero-day flaw that attackers are actively exploiting in the wild. The vulnerability, tracked as CVE-2025-20393, currently has no available patch, leaving organizations exposed to potential compromise. According to threat intelligence from Shadowserver […]

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This article is one source in a clustered incident — the cluster page carries the summary, timeline and every other outlet covering it.

Cisco Email Security Products Targeted in Zero-Day Campaign by China-Linked Actors Cisco has confirmed a zero-day vulnerability (CVE-2025-20393) in its Secure Email appliances that is being exploited by actors linked to China. The attackers have deployed the Aquashell backdoor to establish persistence within affected systems. 6 sources 67

Extracted Entities

100+ Cisco Secure Email Devices Exposed to Zero‑Day Exploited in the Wild

The full story

Extracted Entities

Attack Types (1)

CVEs (1)

Platforms (2)