CVE-2024-20454: Cisco Spa 301 Firmware

Critical severity, CVSS 9.8. EPSS: 6.6% chance of exploitation in the next 30 days.

Multiple vulnerabilities in the web-based management interface of Cisco Small Business SPA300 Series IP Phones and Cisco Small Business SPA500 Series IP Phones could allow an unauthenticated, remote attacker to execute arbitrary commands on the underlying operating system with root privileges. These vulnerabilities exist because incoming HTTP packets are not properly checked for errors, which could result in a buffer overflow. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to overflow an internal buffer and execute arbitrary commands at the root privilege level.

Affected products

• Cisco Spa 301 Firmware: any version
• Cisco Spa 303 Firmware: any version
• Cisco Spa 501g Firmware: any version
• Cisco Spa 502g Firmware: any version
• Cisco Spa 504g Firmware: any version
• Cisco Spa 508g Firmware: any version
• Cisco Spa 509g Firmware: any version
• Cisco Spa 512g Firmware: any version
• Cisco Spa 514g Firmware: any version
• Cisco Spa 525g2 Firmware: any version
• Cisco Spa 525g Firmware: any version

Published 2024-08-07. Last modified 2026-06-17.