Background exploitation KEV catalog No authentication
CVE-2025-20393

Cisco Multiple Products Improper Input Validation Vulnerability

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…

CheckOps priority index
7.4/10 Patch within 7 days
Severity10.0
Probability3.2
Exploitation4/5

Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.

EPSS · today 32.4% higher than 98.3% of CVEs
CVSS 3.1 10.0 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:
Exploited for 321 days 17 Dec 2025
CISA due date 24 Dec 2025 for US federal agencies

Exploitation probability EPSS · FIRST

05010025 Sep05 Oct15 Oct24 Oct02 Nov
EPSS probability (%)Percentile among all CVEs

Exploitation signals 4 / 5

  • KEV catalog (CISA)17 Dec 2025
  • Exploited in EUVD (ENISA)17 Dec 2025
  • Used by ransomwareno
  • EPSS above 10 %32.4%
  • No account, over the networkyes

What to do

Fix

Apply the vendor’s fix as soon as it is available.

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

Meanwhile

Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.

Manufacturers (CRA)

Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained

Description ENISA EUVD

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 products

Cisco Secure Email and Web ManagerCisco Secure EmailMultiple Products
Affected versions
  • 13.6.2-078
  • 13.6.1-201
  • 13.8.1-052
  • 12.8.1-021
  • 14.0.0-404
  • 14.3.0-032
  • 15.5.3-022
  • 13.0.0-392
  • 13.0.0-277
  • 16.0.0-054
  • 15.0.0-104
  • 15.5.2-018
Weaknesses (CWE)

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

  1. Published

  2. Exploitation reported (ENISA)

  3. Added to the KEV catalog

  4. CISA remediation due date

  5. EPSS peak: 32.4%

References

Other exploited vulnerabilities from the same vendor

  • CVE-2026-76418Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference Vulnerability
    5.3 · Rising fast
  • CVE-2026-76519Cisco Secure Email Gateway Relative Path Traversal Vulnerability
    5.8 · Rising fast
  • CVE-2026-76504Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability
    7.5 · Actively exploited
  • CVE-2026-76460Cisco Identity Services Engine Incorrect Use of Privileged APIs Vulnerability
    8.7 · Actively exploited
  • CVE-2026-76461Cisco Secure Email Gateway SQL Injection Vulnerability
    7.2 · Actively exploited
  • CVE-2026-20079Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel Vulnerability
    9.1 · Actively exploited

Are you affected?

CheckOps reads your SBOMs and scans, and alerts you as soon as one of your dependencies is exploited.

Get notified at launch

Sources: CISA KEV · ENISA EUVD · FIRST EPSS · OSV. Public data aggregated by CheckOps, updated automatically. Source texts remain the property of their authors. All exploited vulnerabilities