CVE-2023-20134Network attack vector

Arbitrary file upload via unvalidated HTML request

Published Apr 5, 2023 · Updated Oct 25, 2024

Improper input validation in Cisco Webex Meetings allows remote authenticated users to upload arbitrary files as recordings. The cloud service processes a crafted HTML request without sufficiently validating its user-supplied input before storing the submitted file as a recording. A valid account is required, and the demonstrated consequence is an unauthorized file stored in the meeting service rather than script execution or host compromise.

CVSS severity4.3
Medium
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Cisco Webex Meetings allows remote authenticated users to upload arbitrary files as recordings. The cloud service processes a crafted HTML request without sufficiently validating its user-supplied input before storing the submitted file as a recording. A valid account is required, and the demonstrated consequence is an unauthorized file stored in the meeting service rather than script execution or host compromise.

The record

CVE
CVE-2023-20134
Published
Apr 5, 2023
Updated
Oct 25, 2024
Vendor
ClamAV
Product
Webex Meetings
Classifications
CWE-20, CWE-434, T1105
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 5, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 25, 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=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ClamAV · Webex Meetingsversion=n/a

Published CVSS scores

4.3Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
6.5NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
CWE-434Unrestricted Upload of File with Dangerous Type
T1105Ingress Tool Transfer

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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