CVE-2025-20393Known exploitationNetwork attack vector

Unauthenticated root command execution via crafted HTTP requests

Published Dec 17, 2025 · Updated Dec 17, 2025

Improper input validation in Cisco Secure Email products allows remote attackers to execute arbitrary commands as root through crafted HTTP requests. The AsyncOS Spam Quarantine feature insufficiently validates HTTP requests before passing attacker-controlled input into system-command execution. Exposure requires a vulnerable physical or virtual appliance with the nondefault Spam Quarantine feature enabled and internet-reachable; exploitation grants full operating-system control and supports persistent remote access.

CVSS severity10.0
Critical
EPSS probability29.88%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Cisco Secure Email products allows remote attackers to execute arbitrary commands as root through crafted HTTP requests. The AsyncOS Spam Quarantine feature insufficiently validates HTTP requests before passing attacker-controlled input into system-command execution. Exposure requires a vulnerable physical or virtual appliance with the nondefault Spam Quarantine feature enabled and internet-reachable; exploitation grants full operating-system control and supports persistent remote access.

The record

CVE
CVE-2025-20393
Published
Dec 17, 2025
Updated
Dec 17, 2025
Vendor
ClamAV
Product
Cisco Secure Email
Classifications
CWE-20, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 17, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 17, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=13.0.0-392
  2. Affected versionversion=13.0.5-007
  3. Affected versionversion=13.5.1-277
  4. Affected versionversion=13.5.4-038
  5. Affected versionversion=14.0.0-698
  6. Affected versionversion=14.2.0-620
  7. Affected versionversion=14.2.1-020
  8. Affected versionversion=14.3.0-032
  9. Affected versionversion=15.0.0-104
  10. Affected versionversion=15.0.1-030
  11. Affected versionversion=15.0.3-002
  12. Affected versionversion=15.5.0-048
  13. Affected versionversion=15.5.1-055
  14. Affected versionversion=15.5.2-018
  15. Affected versionversion=15.5.3-022
  16. Affected versionversion=16.0.0-050
  17. Affected versionversion=16.0.0-054
  18. Affected versionversion=16.0.1-017

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Secure Emailversion=13.0.0-392; version=13.0.5-007; version=13.5.1-277; version=13.5.4-038; version=14.0.0-698; version=14.2.0-620; version=14.2.1-020; version=14.3.0-032; version=15.0.0-104; version=15.0.1-030; version=15.0.3-002; version=15.5.0-048; version=15.5.1-055; version=15.5.2-018; version=15.5.3-022; version=16.0.0-050; version=16.0.0-054; version=16.0.1-017
ClamAV · Cisco Secure Email and Web Managerversion=12.8.1-002; version=12.8.1-021; version=13.0.0-249; version=13.0.0-277; version=13.6.1-201; version=13.6.2-023; version=13.6.2-078; version=13.8.1-052; version=13.8.1-068; version=13.8.1-074; version=13.8.1-108; version=14.0.0-404; version=14.1.0-227; version=14.2.0-203; version=14.2.0-212; version=14.2.0-224; version=14.3.0-120; version=15.0.0-334; version=15.0.1-035; version=15.5.1-024; version=15.5.1-029; version=15.5.2-005; version=15.5.3-017; version=16.0.0-195; version=16.0.1-010; version=16.0.2-088

Published CVSS scores

10.0CiscoCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

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Your stack

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