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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-20271 Detail

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 denial of service (DoS) condition in the Cisco AnyConnect service on an affected device. This vulnerability is due to variable initialization errors when an SSL VPN session is established. An attacker could exploit this vulnerability by sending a sequence of crafted HTTPS requests to an affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to restart, resulting in the failure of all established SSL VPN sessions 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, effectively making the Cisco AnyConnect VPN service unavailable for all legitimate users.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-sM5GCfm7

Weakness Enumeration

CWE-ID CWE Name Source
CWE-457 Use of Uninitialized Variable Cisco Systems, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-20271
NVD Published Date:
06/18/2025
NVD Last Modified:
06/23/2025
Source:
Cisco Systems, Inc.