CVE-2021-1351Network attack vector

Browser-context script execution via unvalidated web input

Published Feb 17, 2021 · Updated Nov 8, 2024

Cross-site scripting in Cisco Webex Meetings allows remote attackers to run script in a user's browser through a crafted link. The cloud service's web interface insufficiently validates user-supplied input, allowing that input to be interpreted as script code in the affected interface. Exploitation requires a user to click the malicious link and permits browser-context script execution or access to sensitive browser-based information.

CVSS severity6.1
Medium
EPSS probability0.81%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Cisco Webex Meetings allows remote attackers to run script in a user's browser through a crafted link. The cloud service's web interface insufficiently validates user-supplied input, allowing that input to be interpreted as script code in the affected interface. Exploitation requires a user to click the malicious link and permits browser-context script execution or access to sensitive browser-based information.

The record

CVE
CVE-2021-1351
Published
Feb 17, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Webex Meetings
Classifications
CWE-80, CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 17, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 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 privilegesunauthenticated

What is affected?

ClamAV · Webex Meetingsversion=n/a

Published CVSS scores

6.1Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:X/RL:X/RC:X
4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-80Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
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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