CVE-2024-20257Network attack vector

Stored XSS via insufficient input validation

Published May 15, 2024 · Updated Aug 1, 2024

Stored XSS in Cisco Secure Email Gateway AsyncOS allows remote authenticated users to run script in another interface user's browser. The web-based management interface insufficiently validates attacker-controlled input, allowing stored content to execute when a crafted link is opened. Exploitation requires high-privilege interface access and a second user's interaction; successful attacks expose sensitive browser-based information.

CVSS severity4.8
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Cisco Secure Email Gateway AsyncOS allows remote authenticated users to run script in another interface user's browser. The web-based management interface insufficiently validates attacker-controlled input, allowing stored content to execute when a crafted link is opened. Exploitation requires high-privilege interface access and a second user's interaction; successful attacks expose sensitive browser-based information.

The record

CVE
CVE-2024-20257
Published
May 15, 2024
Updated
Aug 1, 2024
Vendor
ClamAV
Product
Cisco Secure Email
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 15, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 1, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=11.0.3-238
  2. Affected versionversion=11.1.0-069
  3. Affected versionversion=11.1.0-128
  4. Affected versionversion=11.1.0-131
  5. Affected versionversion=12.0.0-419
  6. Affected versionversion=12.1.0-071
  7. Affected versionversion=12.1.0-087
  8. Affected versionversion=12.1.0-089
  9. Affected versionversion=12.5.0-066
  10. Affected versionversion=12.5.3-041
  11. Affected versionversion=12.5.4-041
  12. Affected versionversion=13.0.0-392
  13. Affected versionversion=13.0.5-007
  14. Affected versionversion=13.5.1-277
  15. Affected versionversion=13.5.4-038
  16. Affected versionversion=14.0.0-698
  17. Affected versionversion=14.2.0-620
  18. Affected versionversion=14.2.1-020
  19. Affected versionversion=14.3.0-032
  20. Affected versionversion=15.0.0-104
  21. Affected versionversion=15.0.1-030
  22. Affected versionversion=15.5.0-048

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ClamAV · Cisco Secure Emailversion=11.0.3-238; version=11.1.0-069; version=11.1.0-128; version=11.1.0-131; version=12.0.0-419; version=12.1.0-071; version=12.1.0-087; version=12.1.0-089; version=12.5.0-066; version=12.5.3-041; version=12.5.4-041; version=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=15.5.0-048

Published CVSS scores

4.8CiscoCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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.

Technologies

Your stack

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Your stack

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