CVE-2021-1478: Cisco Unified Communications Manager Denial of Service Vulnerability

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-05-06 · updated 2026-06-17
Weakness: CWE-284

Description

A vulnerability in the Java Management Extensions (JMX) component of Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected system. This vulnerability is due to an unsecured TCP/IP port. An attacker could exploit this vulnerability by accessing the port and restarting the JMX process. A successful exploit could allow the attacker to cause a DoS condition on an affected system.

Affected products

Cisco Hosted Collaboration Mediation Fulfillment: before 12.6 — fixed in 12.6
Cisco Unified Communications Manager: before 12.6 — fixed in 12.6

How to fix

Upgrade to a fixed version: Cisco Hosted Collaboration Mediation Fulfillment 12.6; Cisco Unified Communications Manager 12.6. Check the vendor advisory for mitigations.

References

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