Cisco Unified Communications Manager contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service condition on a targeted device. Updates are available.
Cisco Unified Communications Manager contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.
The vulnerability is due to insufficient traffic rate-limiting on the session initiation protocol (SIP) port. An attacker could exploit this vulnerability by sending UDP packets at a high rate to port 5060 on targeted device. A sustained attack could allow the attacker to cause a DoS condition on the device.
Cisco has confirmed the vulnerability in a security advisory and has released software updates.
Cisco Unified Communications Manager versions 8.5(x), 8.6(x) and 9.0(1) are affected.
To exploit this vulnerability, an attacker may require access to trusted, internal networks to send crafted requests to the affected software. This access requirement could limit the likelihood of a successful exploit.
Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
Software updates for Cisco Unified Communications Manager version 8.5(x) were not available at the time this alert was first published. Customers running version 8.5(0) are advised to upgrade to 8.6(0).
An unauthenticated, remote attacker could exploit this vulnerability to cause a DoS condition on a targeted device.
The vulnerability is due to insufficient rate limiting of traffic on the SIP port by the affected software.
An attacker could exploit the vulnerability by sending UDP packets at a high rate to port 5060 on a device running the affected software. When the UDP packets are processed, a memory leak and high CPU utilization could occur. A sustained attack could allow the attacker to cause a DoS condition on the affected device.
Administrators are advised to apply the appropriate updates.
Administrators are advised to contact the vendor regarding future updates and releases.
Administrators are advised to allow only trusted users to have network access.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
Administrators are advised to monitor affected systems.
Cisco customers with active contracts can obtain updates through the Software Center at the following link: Cisco
Cisco customers without contracts can obtain upgrades by contacting the Cisco Technical Assistance Center at 1-800-553-2447 or 1-408-526-7209 or via email at email@example.com
The security vulnerability applies to the following combinations of products.
Cisco Unified Communications Manager
8.5 Base | 8.6 Base | 9.0 Base
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