CVEs / CVE-2025-20393
CVE-2025-20393: Cisco Multiple Products Improper Input Validation Vulnerability
- Known exploited in the CISA KEV catalog since 17 Dec 2025
- critical 10 CVSS 3.1 (from the CNA)
- EPSS 32.3% chance of exploitation in the next 30 days, higher than 98% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
Description
A vulnerability in the Spam Quarantine feature of Cisco AsyncOS Software for Cisco Secure Email Gateway and Cisco Secure Email and Web Manager could allow an unauthenticated, remote attacker to execute arbitrary system commands on an affected device with root privileges. This vulnerability is due to insufficient validation of HTTP requests by the Spam Quarantine feature. An attacker could exploit this vulnerability by sending a crafted HTTP request to the affected device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system with root privileges.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Cisco Cisco Secure Email | 14.0.0-698 | — |
| Cisco Cisco Secure Email | 13.5.1-277 | — |
| Cisco Cisco Secure Email | 13.0.0-392 | — |
| Cisco Cisco Secure Email | 14.2.0-620 | — |
| Cisco Cisco Secure Email | 13.0.5-007 | — |
| Cisco Cisco Secure Email | 13.5.4-038 | — |
| Cisco Cisco Secure Email | 14.2.1-020 | — |
| Cisco Cisco Secure Email | 14.3.0-032 | — |
| Cisco Cisco Secure Email | 15.0.0-104 | — |
| Cisco Cisco Secure Email | 15.0.1-030 | — |
| Cisco Cisco Secure Email | 15.5.0-048 | — |
| Cisco Cisco Secure Email | 15.5.1-055 | — |
| Cisco Cisco Secure Email | 15.5.2-018 | — |
| Cisco Cisco Secure Email | 16.0.0-050 | — |
| Cisco Cisco Secure Email | 15.0.3-002 | — |
| Cisco Cisco Secure Email | 16.0.0-054 | — |
| Cisco Cisco Secure Email | 15.5.3-022 | — |
| Cisco Cisco Secure Email | 16.0.1-017 | — |
| Cisco Cisco Secure Email and Web Manager | 13.6.2-023 | — |
| Cisco Cisco Secure Email and Web Manager | 13.6.2-078 | — |
| Cisco Cisco Secure Email and Web Manager | 13.0.0-249 | — |
| Cisco Cisco Secure Email and Web Manager | 13.0.0-277 | — |
| Cisco Cisco Secure Email and Web Manager | 13.8.1-052 | — |
| Cisco Cisco Secure Email and Web Manager | 13.8.1-068 | — |
| Cisco Cisco Secure Email and Web Manager | 13.8.1-074 | — |
| Cisco Cisco Secure Email and Web Manager | 14.0.0-404 | — |
| Cisco Cisco Secure Email and Web Manager | 12.8.1-002 | — |
| Cisco Cisco Secure Email and Web Manager | 14.1.0-227 | — |
| Cisco Cisco Secure Email and Web Manager | 13.6.1-201 | — |
| Cisco Cisco Secure Email and Web Manager | 14.2.0-203 | — |
Exploitation
| In CISA KEV since | 17 Dec 2025 |
|---|---|
| Due date for US federal agencies | 24 Dec 2025 |
| Used in ransomware campaigns | Unknown |
| 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. |
Severity
| CVSS 3.1 | 10 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-20 |
References
- CVE-2025-20393 on NVD
- CVE-2025-20393 in the CISA KEV catalog
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sma-attack-N9bf4 (cited by CISA)
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sma-attack-N9bf4 Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-20393 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.