CVE-2020-3164Network attack vector

Service degradation via malformed HTTP headers

Published Mar 4, 2020 · Updated Nov 15, 2024

Denial of service in Cisco Secure Web Appliance 12.0.1-268 and earlier allows remote attackers to degrade GUI performance. The AsyncOS web management interface fails to validate specific HTTP headers before processing a malformed request, driving its GUI processes into prolonged high CPU utilization. No authentication is required; the appliance remains operative, but response times and overall performance degrade.

CVSS severity5.3
Medium
EPSS probability1.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Cisco Secure Web Appliance 12.0.1-268 and earlier allows remote attackers to degrade GUI performance. The AsyncOS web management interface fails to validate specific HTTP headers before processing a malformed request, driving its GUI processes into prolonged high CPU utilization. No authentication is required; the appliance remains operative, but response times and overall performance degrade.

The record

CVE
CVE-2020-3164
Published
Mar 4, 2020
Updated
Nov 15, 2024
Vendor
ClamAV
Product
Cisco Secure Web Appliance
Classifications
CWE-20, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 4, 2020CVE publishedPublication date reported by the CVE source.
  2. Nov 15, 2024Record 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=unspecified <n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Secure Web Applianceversion=unspecified <n/a

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
5.3Cisco Systems, Inc.CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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 exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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