CVE-2021-1517Network attack vector

File-warning bypass via unsafe multimedia sharing

Published Jun 4, 2021 · Updated Nov 7, 2024

Security bypass in Cisco Webex Meetings Server before 3.0 MR4 and before 4.0 MR4 allows remote authenticated users to suppress file warnings. The multimedia viewer unsafely handles a file shared into a meeting, causing warning dialogs to be omitted before the file is offered. The attacker must be authenticated and able to share a file, and the documented result is limited to suppressing warnings shown to other users.

CVSS severity5.0
Medium
EPSS probability0.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Security bypass in Cisco Webex Meetings Server before 3.0 MR4 and before 4.0 MR4 allows remote authenticated users to suppress file warnings. The multimedia viewer unsafely handles a file shared into a meeting, causing warning dialogs to be omitted before the file is offered. The attacker must be authenticated and able to share a file, and the documented result is limited to suppressing warnings shown to other users.

The record

CVE
CVE-2021-1517
Published
Jun 4, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Cisco WebEx Meetings Server
Classifications
CWE-693
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 4, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 7, 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 · Cisco WebEx Meetings Serverversion=n/a

Published CVSS scores

5.0CiscoCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N/E:X/RL:X/RC:X

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-693Protection Mechanism Failure

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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