Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since December 17, 2025.
CVE-2025-20393
Cisco Multiple Products Improper Input Validation Vulnerability
Added to KEV December 17, 2025
Alert details
- Source feed
- CISA KEV
- CVE ID
- CVE-2025-20393
- CWE
- CWE-20
- Affected products
- Multiple Products · Cisco Multiple Products · Cisco
What happened
Cisco Secure Email Gateway, Secure Email, AsyncOS Software, and Web Manager appliances contains an improper input validation vulnerability that allows threat actors to execute arbitrary commands with root privileges on the underlying operating system of an affected appliance.
What it means for your business
Cisco Multiple Products is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2025-20393). Cisco Secure Email Gateway, Secure Email, AsyncOS Software, and Web Manager appliances contains an improper input validation vulnerability that allows threat actors to execute arbitrary commands with root privileges on the underlying operating system of an affected appliance. CISA remediation due date: 2025-12-24. If you need help checking exposure, call (864) 335-9223.
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA due date: December 24, 2025
Sources
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