Cisco Meraki MX and Z Series AnyConnect VPN with Client Certificate Authentication Denial of Service Vulnerability (Cisco Cisco Meraki MX Firmware)

CVE-2025-20271
HIGH 8.6

At a glance

Source
NVD
EPSS
EPSS 0.54 % · percentile 45 ()
State
PUBLISHED
Published
Updated
Assigner
cisco
NVD status
Deferred

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.

Weaknesses (CWE)

  • CWE-457 — Use of Uninitialized Variable

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 8.6CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hcisco
CVSS 3.1HIGH 8.6CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:HNVD · psirt@cisco.com (Secondary)

European references

CERT-FR advisories

Affected products

ProductVersions
Cisco · Cisco Meraki MX Firmwareaffected N/A

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD