CVE-2024-20502 Denial of service in Cisco Meraki MX Firmware

Medium 5.8 Published Updated

Unauthenticated remote attackers can cause a denial of service on Cisco Meraki MX and Z Series devices by exhausting resources during SSL VPN session establishment.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Over the internet
Victim action needed
Not needed
Fix
None listed

What is CVE-2024-20502?

CVE-2024-20502 is a medium-severity denial of service vulnerability in Cisco Meraki MX Firmware, published on 2 Oct 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability 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 on an affected device.

This vulnerability is due to insufficient resource management while establishing SSL VPN sessions. An attacker could exploit this vulnerability by sending a series of crafted HTTPS requests to the VPN server of an affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to stop accepting new connections, preventing new SSL VPN connections from being established. Existing SSL VPN sessions are not impacted.

Note: When the attack traffic stops, the Cisco AnyConnect VPN server recovers gracefully without requiring manual intervention.

Weakness: CWE-400

Which versions are affected by CVE-2024-20502?

It affects 25 products.

Products include Cisco Meraki Mx100 Firmware, Cisco Meraki Mx105 Firmware, Cisco Meraki Mx250 Firmware, Cisco Meraki Mx400 Firmware, Cisco Meraki Mx450 Firmware, Cisco Meraki Mx600 Firmware and 19 more.

How do I fix CVE-2024-20502?

No fix has been published for CVE-2024-20502 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2024-20502 being exploited?

There is no known exploitation of CVE-2024-20502 in the wild and no public exploit code.

Sources

Also known as GHSA-2r9m-635c-rmwj.

Is CVE-2024-20502 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free