High severity · published Oct 2, 2024
CVE-2024-20499
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…
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 43% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CM
Cisco Meraki MX Firmware · Cisco
All versions, or not specified · source: vendor
MM
Meraki Mx100 Firmware · Cisco
16.2 before 18.211.2 · source: NVD
MM
Meraki Mx105 Firmware · Cisco
16.2 before 18.211.2 · source: NVD
MM
Meraki Mx250 Firmware · Cisco
16.2 before 18.211.2 · source: NVD
MM
Meraki Mx400 Firmware · Cisco
16.2 before 18.211.2 · source: NVD
MM
Meraki Mx450 Firmware · Cisco
16.2 before 18.211.2 · source: NVD
MM
Meraki Mx600 Firmware · Cisco
16.2 before 18.211.2 · source: NVD
MM
Meraki Mx64 Firmware · Cisco
17.6.0 through 18.211.2 · source: NVD
MM
Meraki Mx64w Firmware · Cisco
16.2 before 18.211.2 · source: NVD
MM
Meraki Mx65 Firmware · Cisco
17.6.0 before 18.211.2 · source: NVD
MM
Meraki Mx65w Firmware · Cisco
16.2 before 18.211.2 · source: NVD
MM
Meraki Mx67 Firmware · Cisco
16.2 before 18.211.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2024-20499
CVE.org
https://www.cve.org/CVERecord?id=CVE-2024-20499
Vendor Advisory
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-QTRHzG2
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