Cisco Secure Email/Secure Email and Web Manager input validation

CVSS Meta Temp Score
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CTI Interest Score
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9.7$5k-$25k0.00

Summaryinfo

A vulnerability identified as very critical has been detected in Cisco Secure Email and Secure Email and Web Manager. This issue affects some unknown processing. The manipulation leads to input validation. This vulnerability is traded as CVE-2025-20393. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in Cisco Secure Email and Secure Email and Web Manager (affected version not known). This issue affects some unknown functionality. The manipulation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at sec.cloudapps.cisco.com. The identification of this vulnerability is CVE-2025-20393 since 10/10/2024. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are unknown but an exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 03/19/2026).

It is declared as attacked. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 12/17/2025 with a due date of 12/24/2025:

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at Zero-Day.cz (1060), EUVD (EUVD-2025-203911) and CERT Bund (WID-SEC-2025-2870). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Cisco AsyncOS
  • Cisco Secure Email Gateway

Productinfo

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.7

VulDB Base Score: 9.8
VulDB Temp Score: 9.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 10.0
CNA Vector (cisco): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Attacked

EPSS Score: 🔒
EPSS Percentile: 🔒

KEV Added: 🔒
KEV Due: 🔒
KEV Remediation: 🔒
KEV Ransomware: 🔒
KEV Notice: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Zero-Day.cz: 🔒

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

10/10/2024 CVE reserved
12/17/2025 +433 days Advisory disclosed
12/17/2025 +0 days VulDB entry created
03/19/2026 +92 days VulDB entry last update

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-sma-attack-N9bf4
Status: Confirmed

CVE: CVE-2025-20393 (🔒)
GCVE (CVE): GCVE-0-2025-20393
GCVE (VulDB): GCVE-100-336989
EUVD: 🔒
CERT Bund: WID-SEC-2025-2870 - Cisco AsyncOS für Secure Email Gateway: Schwachstelle ermöglicht Ausführen von beliebigem Programmcode mit Administratorrechten

scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 12/17/2025 18:38
Updated: 03/19/2026 19:20
Changes: 12/17/2025 18:38 (61), 12/17/2025 23:32 (13), 12/18/2025 07:09 (1), 12/18/2025 15:49 (1), 12/20/2025 07:47 (1), 12/21/2025 20:23 (6), 01/15/2026 18:29 (1), 03/19/2026 19:20 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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