CVE-2024-20499: cisco cisco meraki mx firmware Out-of-bounds Write

Vulnerability summary

CVE-2024-20499 is a high (CVSS 8.6) Out-of-bounds Write vulnerability in cisco cisco meraki mx firmware. EPSS estimates a 0.51% chance of exploitation in the next 30 days, higher than 41.8% of scored vulnerabilities.

Timeline

1. 02-10-2024
   PublishedVulnerability first disclosed.
2. 04-06-2025
   Last modifiedVulnerability information updated.

Description

Multiple vulnerabilities in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z Series Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a DoS condition in the AnyConnect service on an affected device. These vulnerabilities are due to insufficient validation of client-supplied parameters while establishing an SSL VPN session. An attacker could exploit these vulnerabilities by sending a crafted HTTPS request to the VPN server of an affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to restart, resulting in the failure of the established SSL VPN connections and forcing remote users to initiate a new VPN connection and reauthenticate. A sustained attack could prevent new SSL VPN connections from being established. Note: When the attack traffic stops, the Cisco AnyConnect VPN server recovers gracefully without requiring manual intervention.

• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.