CVE-2022-20933
highpriority · track · 34EPSS 0.011 · 67 %ileEURUUSEPSS · scored 2026-10-27
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.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Meraki MX Firmwarecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (50)
Products and version ranges known to be affected.
- cisco meraki mx100 firmware16.2.0 → 16.16.6nvdUScpe:2.3:o:cisco:meraki_mx100_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx100 firmware17.0.0 → 17.10.1nvdUScpe:2.3:o:cisco:meraki_mx100_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx105 firmware16.2.0 → 16.16.6nvdUScpe:2.3:o:cisco:meraki_mx105_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx105 firmware17.0.0 → 17.10.1nvdUScpe:2.3:o:cisco:meraki_mx105_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx250 firmware16.2.0 → 16.16.6nvdUScpe:2.3:o:cisco:meraki_mx250_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx250 firmware17.0.0 → 17.10.1nvdUScpe:2.3:o:cisco:meraki_mx250_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx400 firmware16.2.0 → 16.16.6nvdUScpe:2.3:o:cisco:meraki_mx400_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx400 firmware17.0.0 → 17.10.1nvdUScpe:2.3:o:cisco:meraki_mx400_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx450 firmware16.2.0 → 16.16.6nvdUScpe:2.3:o:cisco:meraki_mx450_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx450 firmware17.0.0 → 17.10.1nvdUScpe:2.3:o:cisco:meraki_mx450_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx600 firmware16.2.0 → 16.16.6nvdUScpe:2.3:o:cisco:meraki_mx600_firmware:*:*:*:*:*:*:*:*
- cisco meraki mx600 firmware17.0.0 → 17.10.1nvdUScpe:2.3:o:cisco:meraki_mx600_firmware:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-meraki-mx-vpn-dos-vnESbgBfCisco Meraki MX and Z3 Teleworker Gateway VPN Denial of Service Vulnerability2022-10-19csaf · cisco_csafUS
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. There are no workarounds that address this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (5)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2022-20933/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-vnESbgBfcnnvd
- https://vigilance.fr/vulnerability/Cisco-Meraki-MX-denial-of-service-via-TLS-39652cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-vnESbgBfenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-vnESbgBfVendor Advisorynvd
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