CVE-2025-20393

Product

Cisco / Multiple Products

Vulnerability

Cisco Multiple Products Improper Input Validation Vulnerability

Added to KEV

Dec 17, 2025

Remediate by

Dec 24, 2025

Known ransomware use

No

Summary description

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.

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.

Notes

Please adhere to Cisco's guidelines to assess exposure and mitigate risks. Check for signs of potential compromise on all internet accessible Cisco products affected by this vulnerability. Apply any final mitigations provided by the vendor as soon as they become available. For more information please see: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sma-attack-N9bf4 ; https://nvd.nist.gov/vuln/detail/CVE-2025-20393