What’s Vulnerable › Vulnerabilities

CVE-2023-20259

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-10-04 · updated 2026-06-17
• Weakness: CWE-400

Description

A vulnerability in an API endpoint of multiple Cisco Unified Communications Products could allow an unauthenticated, remote attacker to cause high CPU utilization, which could impact access to the web-based management interface and cause delays with call processing. This API is not used for device management and is unlikely to be used in normal operations of the device. This vulnerability is due to improper API authentication and incomplete validation of the API request. An attacker could exploit this vulnerability by sending a crafted HTTP request to a specific API on the device. A successful exploit could allow the attacker to cause a denial of service (DoS) condition due to high CPU utilization, which could negatively impact user traffic and management access. When the attack stops, the device will recover without manual intervention.

Affected products

• Cisco Emergency Responder: 14su3
• Cisco Prime Collaboration Deployment: 14su3
• Cisco Unified Communications Manager: 12.5(1)su7, 14su3
• Cisco Unified Communications Manager Im & Presence Service: 12.5(1)su7, 14su3
• Cisco Unity Connection: 14su3

References

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-apidos-PGsDcdNF
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-apidos-PGsDcdNF

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