Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2025-20393

Cisco Secure Email

Cisco Secure Email · 14.0.0-698

Watch CVE-2025-20393 Browse KEV feed
Severity
CVSS 10.0 · Critical
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
32.4%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2025-20393 is an unauthenticated vulnerability affecting Cisco Secure Email, Cisco Secure Email and Web Manager. A vulnerability in the Spam Quarantine feature of Cisco AsyncOS Software for Cisco Secure Email...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

Cisco Secure Email 14.0.0-698.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

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.

Cisco Affected
Cisco Secure Email
14.0.0-698 13.5.1-277 13.0.0-392 14.2.0-620 13.0.5-007 13.5.4-038 14.2.1-020 14.3.0-032 15.0.0-104 15.0.1-030 15.5.0-048 15.5.1-055 15.5.2-018 16.0.0-050 15.0.3-002 16.0.0-054 15.5.3-022 16.0.1-017
Cisco Affected
Cisco Secure Email and Web Manager
13.6.2-023 13.6.2-078 13.0.0-249 13.0.0-277 13.8.1-052 13.8.1-068 13.8.1-074 14.0.0-404 12.8.1-002 14.1.0-227 13.6.1-201 14.2.0-203 14.2.0-212 12.8.1-021 13.8.1-108 14.2.0-224 14.3.0-120 15.0.0-334 15.5.1-024 15.5.1-029 15.5.2-005 16.0.0-195 15.5.3-017 16.0.1-010 15.0.1-035 16.0.2-088
Published
17 Dec 2025
Exploitation Reported
01 Jun 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

cisa edge

CVE References

  • CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2025-20393
  • cisco-sa-sma-attack-N9bf4 sec.cloudapps.cisco.com · CVE Record https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurity...

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CVE

Recorded 01 Jun 2026

A trusted third party reported exploitation.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
CVE First 2026-06-01 10:46 UTC
CISA 2026-06-02 14:04 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

No detection artifacts or sensor request patterns are available for this CVE yet.

Check back as sensor telemetry and scanner integrations are updated.

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

10.0 Critical

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

EPSS

32.4%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Input Validation CWE-20

Recent mention · TheRegister

Cisco email security boxes can be rooted by... an email

Attackers already exploiting the critical flaw, and Cisco warns they may be able to cover their tracks once they're in

Read full advisory

Timeline

From disclosure to observed exploitation

  1. 14:04 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  2. 10:46 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  3. 16:47 UTC

    CVE published

    Vulnerability disclosed publicly

  4. 19:15 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2025-20393

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2025-20393",
  "confidence": "Confirmed",
  "cvss_score": 10.0,
  "cvss_estimated": false,
  "epss_score": 0.32392,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}