CVE-2022-20933: A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z3 Teleworker Gateway devices could allow an unauthenticated, r...

Description

A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z3 Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of client-supplied parameters while establishing an SSL VPN session. An attacker could exploit this vulnerability by crafting a malicious request and sending it to the affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to crash and restart, resulting in the failure of the established SSL VPN connections and forcing remote users to initiate a new VPN connection and re-authenticate. 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. Cisco Meraki has released software updates that address this vulnerability.

Metrics

CVSS 3.1

8.6/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS Probability

0.99%

58.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-234

Affected Software

Vendor	Product	Versions
Cisco	Meraki Mx64 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx64 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx64w Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx64w Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx65 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx65 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx65w Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx65w Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx67 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx67 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx67cw Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx67cw Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx67w Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx67w Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx68 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx68 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx68cw Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx68cw Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx68w Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx68w Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx75 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx75 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx84 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx84 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx85 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx85 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx95 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx95 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx100 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx100 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx105 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx105 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx250 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx250 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx400 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx400 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx450 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx450 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Mx600 Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Mx600 Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Vmx Firmware	>= 16.2.0, < 16.16.6
Cisco	Meraki Vmx Firmware	>= 17.0.0, < 17.10.1
Cisco	Meraki Z3c Firmware	All versions
Cisco	Meraki Z3 Firmware	All versions

References

Timeline

Published: Oct 26, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2022-20933?

A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z3 Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of client-supplied parameters while establishing an SSL VPN session. An attacker could exploit this vulnerability by crafting a malicious request and sending it to the affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to crash and restart, resulting in the failure of the established SSL VPN connections and forcing remote users to initiate a new VPN connection and re-authenticate. 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. Cisco Meraki has released software updates that address this vulnerability.

How severe is CVE-2022-20933?

CVE-2022-20933 has a CVSS score of 8.6/10 (HIGH severity). The EPSS model estimates a 0.99% probability of exploitation in the next 30 days.

How do I fix CVE-2022-20933?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.