Denial of service in Cisco Meraki MX and Cisco Meraki Z Series Teleworker Gateway devices

1) Race condition

EUVDB-ID: #VU98032

Risk: Medium

CVSSv3.1: 5.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2024-20509

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a race condition during the VPN authentication process. A remote attacker can correctly guess an authentication handler and then send specially crafted HTTPS requests to cause a denial of service condition on the target system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Meraki MX: 16.2 - 18.0

Cisco Meraki MX64: All versions

Cisco Meraki MX64W: All versions

Cisco Meraki MX65: All versions

Cisco Meraki MX65W: All versions

Cisco Meraki MX67: All versions

Cisco Meraki MX67C: All versions

Cisco Meraki MX67W: All versions

Cisco Meraki MX68: All versions

Cisco Meraki MX68CW: All versions

Cisco Meraki MX68W: All versions

Cisco Meraki MX75: All versions

Cisco Meraki MX84: All versions

Cisco Meraki MX85: All versions

Cisco Meraki MX95: All versions

Cisco Meraki MX100: All versions

Cisco Meraki MX105: All versions

Cisco Meraki MX250: All versions

Cisco Meraki MX400: All versions

Cisco Meraki MX450: All versions

Cisco Meraki MX600: All versions

Cisco Meraki vMX: All versions

Cisco Meraki Z3: All versions

Cisco Meraki Z3C: All versions

Cisco Meraki Z4: All versions

Cisco Meraki Z4C: All versions

CPE2.3

• cpe:2.3:h:cisco_systems:meraki_mx:16.2:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:meraki_mx:17.0:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:meraki_mx:18.0:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx64:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx64w:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx65:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx65w:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx67:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx67c:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx67w:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx68:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx68cw:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx68w:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx75:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx84:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx85:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx95:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx100:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx105:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx250:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx400:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx450:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_mx600:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_vmx:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_z3:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_z3c:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_z4:*:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_meraki_z4c:*:*:*:*:*:*:*:

External links

http://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-by-QWUkqV7X

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.