Cisco Multiple Products Improper Input Validation Vulnerability
Cisco — Cisco Secure Email
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.
10.0
29.9%
Vector breakdown
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- Published
- Dec 17, 2025
- Modified
- Jun 17, 2026
- Added to KEV
- Dec 17, 2025
- Federal patch due
- Dec 24, 2025
CISA 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.
Weakness classification
Affected packages
Proof-of-concept & exploitation references
4 foundWeaponization
Public repositories whose name or description references CVE-2025-20393, found via a live GitHub search at request time. These are community-sourced signals, not a verified working exploit - cross-check each one before relying on it, and treat higher star counts and recent activity as (weak) corroboration, not proof.
- cyberleelawat/CVE-2025-20393★ 2
Cisco is aware of a potential vulnerability. Cisco is currently investigating and will update these details as appropriate as more information becomes available.
updated Jan 14, 2026
- redpack-kr/Blackash-CVE-2025-20393★ 0
CVE-2025-20393
updated Dec 28, 2025
- KingHacker353/CVE-2025-20393★ 0
updated Dec 18, 2025
- cyberdudebivash/CYBERDUDEBIVASH-Cisco-AsyncOS-CVE-2025-20393-Scanner★ 0
This tool helps identify exposure to CVE-2025-20393 by checking for open TCP/6025 ports, responsive Spam Quarantine interfaces, and known post-exploitation IOCs.
updated Jan 16, 2026
References
Frequently asked questions
What is CVE-2025-20393?
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.
How severe is CVE-2025-20393?
CVE-2025-20393 has a CVSS base score of 10.0 out of 10 (CVSS 3.1).
Is CVE-2025-20393 actively exploited in the wild?
Yes. CVE-2025-20393 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added Dec 17, 2025, meaning CISA has confirmed evidence of active exploitation.
What is the EPSS score for CVE-2025-20393?
29.9% - meaning FIRST.org's EPSS model estimates a 29.9% probability this vulnerability will be exploited in the wild within 30 days (98% percentile among all scored CVEs).
Is there exploit tooling available for CVE-2025-20393?
We found 4 public GitHub repositories referencing CVE-2025-20393, though none matched a known Nuclei template or Metasploit module at last check. Review each one before relying on it - see the proof-of-concept section above.
What type of vulnerability is CVE-2025-20393?
CVE-2025-20393 is classified under CWE-20 (Improper Input Validation).
Cross-checked against
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