CVE-2019-1887: Cisco Unified Communications Manager

High severity, CVSS 7.5. EPSS: 1.8% chance of exploitation in the next 30 days.

A vulnerability in the Session Initiation Protocol (SIP) protocol implementation of Cisco Unified Communications Manager could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient validation of input SIP traffic. An attacker could exploit this vulnerability by sending a malformed SIP packet to an affected Cisco Unified Communications Manager. A successful exploit could allow the attacker to trigger a new registration process on all connected phones, temporarily disrupting service.

Affected products

• Cisco Unified Communications Manager: version 10.5(2.10000.5) only; version 11.5(1.10000.6) only; version 12.0(1.10000.10) only; version 12.5(1.10000.22) only

Published 2019-07-06. Last modified 2026-06-17.