CVE-2024-20499: Cisco Meraki MX and Z3 Teleworker Gateway AnyConnect VPN Denial of Service Vulnerability
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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2024-20499?
The severity of CVE-2024-20499 is critical as it allows an unauthenticated remote attacker to cause a denial of service in the Cisco AnyConnect VPN service.
How do I fix CVE-2024-20499?
To fix CVE-2024-20499, upgrade affected Cisco Meraki devices to the latest firmware version that addresses the vulnerability.
Which devices are affected by CVE-2024-20499?
Devices affected by CVE-2024-20499 include Cisco Meraki MX and Z Series Teleworker Gateway devices running specific firmware versions between 16.2 and 18.211.2.
What impact does CVE-2024-20499 have on Cisco Meraki devices?
CVE-2024-20499 can lead to a Denial of Service (DoS) condition, disrupting the functionality of the Cisco AnyConnect service on affected devices.
Is there a workaround for CVE-2024-20499?
There are no known workarounds for CVE-2024-20499; the primary mitigation is to apply the recommended firmware updates.