CVE-2025-20212
Cisco AnyConnect VPN Denial of Service Vulnerability
Description
A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z Series devices could allow an authenticated, remote attacker to cause a denial of service (DoS) condition in the Cisco AnyConnect service on an affected device. To exploit this vulnerability, the attacker must have valid VPN user credentials on the affected device. This vulnerability exists because a variable is not initialized when an SSL VPN session is established. An attacker could exploit this vulnerability by supplying crafted attributes while establishing an SSL VPN session with 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 sessions 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 without manual intervention.
INFO
Published Date :
April 2, 2025, 5:15 p.m.
Last Modified :
April 7, 2025, 2:18 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
4.0
Exploitability Score :
3.1
Affected Products
The following products are affected by CVE-2025-20212
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-20212.
| URL | Resource |
|---|---|
| https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-vNRpDvfb |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-20212 vulnerability anywhere in the article.
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Daily CyberSecurity
Top 5 VPN Vulnerabilities in 2025
I. Executive SummaryThe reliance on Virtual Private Networks (VPNs) has grown significantly as organizations embrace remote work and individuals seek enhanced online privacy and security. However, thi ... Read more
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Daily CyberSecurity
Cisco Addresses High Severity Vulnerabilities in Enterprise Chat and Email, and Meraki MX/Z Series Devices
Cisco has released security advisories addressing vulnerabilities in its Enterprise Chat and Email (ECE) product and its Meraki MX and Z Series devices. These vulnerabilities could allow for denial-of ... Read more
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Cyber Security News
Cisco AnyConnect VPN Server Vulnerability Let Attacker Trigger DoS Condition
Cisco disclosed a critical security vulnerability affecting Cisco Meraki MX and Z Series devices, which presents significant risks to enterprise networks. The vulnerability tracked as CVE-2025-20212 a ... Read more
The following table lists the changes that have been made to the
CVE-2025-20212 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Apr. 02, 2025
Action Type Old Value New Value Added Description A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z Series devices could allow an authenticated, remote attacker to cause a denial of service (DoS) condition in the Cisco AnyConnect service on an affected device. To exploit this vulnerability, the attacker must have valid VPN user credentials on the affected device. This vulnerability exists because a variable is not initialized when an SSL VPN session is established. An attacker could exploit this vulnerability by supplying crafted attributes while establishing an SSL VPN session with 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 sessions 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 without manual intervention. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H Added CWE CWE-457 Added Reference https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-vNRpDvfb
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-20212 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-20212
weaknesses.