CVE-2021-40122 - CVE House
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Status published Medium CVE-2021-40122

Cisco Meeting Server Call Bridge Denial of Service Vulnerability

Vulnerability Description

A vulnerability in an API of the Call Bridge feature of Cisco Meeting Server could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper handling of large series of message requests. An attacker could exploit this vulnerability by sending a series of messages to the vulnerable API. A successful exploit could allow the attacker to cause the affected device to reload, dropping all ongoing calls and resulting in a DoS condition.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

Cisco Meeting Server
Vulnerable Versions:
Unknown

Timeline

Official Publish: October 21st, 2021
Last Modified: November 7th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-399

MITRE ATT&CK TTPs

T1499.001 OS Exhaustion Flood
Impact
T1499.002 Service Exhaustion Flood
Impact
T1499.003 Application Exhaustion Flood
Impact
T1499.004 Application or System Exploitation
Impact