TI-2021-17317 Aliases CVE-2021-40122 GHSA-3rqh-cwpr-p993

Cisco Meeting Server Call Bridge Denial of Service Vulnerability

LOW 35CWE-399Published 2021-10-21 · Updated 2024-11-07

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-399 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.01164 67th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Cisco	Cisco Meeting Server	all versions	—	No fix listed	CNA

Cisco Meeting Server VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:cisco:meeting_server::::::::	up to 3.1; 3.2 to before 3.2.3	Vulnerable	Cisco

cpe:2.3:a:cisco:meeting_server:*:*:*:*:*:*:*:* Versions up to 3.1; 3.2 to before 3.2.3 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-40122
2026-10-03 Alias added: GHSA-3rqh-cwpr-p993

References

Advisory 1

20211020 Cisco Meeting Server Call Bridge Denial of Service Vulnerability

TI-2016-05530 Memory corruption in Cisco Meeting Server before 2.0.3 and Acano Server before 1.9.5 CVSS 3.0CRITICAL 9.8
TI-2016-05529 Memory corruption in Cisco Meeting Server before 2.0.1, Acano Server before 1.9.3, Cisco… CVSS 3.0CRITICAL 9.8
TI-2018-00239 Improper input validation in Cisco Meeting Server Media Services CVSS 3.0HIGH 7.5
TI-2017-09025 Exposure of resource to wrong sphere in Cisco Meeting Server CVSS 3.0CRITICAL 9.1
TI-2018-00222 A vulnerability in Cisco Meeting Server could allow an unauthenticated, remote attacker… CVSS 3.0HIGH 8.1
TI-2016-05527 Improper input validation in Cisco Meeting Server before 2.0.6 and Acano Server before… CVSS 3.0CRITICAL 9.1

See all 30 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences