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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-66420 Detail

Description

MeshCentral 1.1.21 contains a cross-site WebSocket hijacking protection bypass vulnerability that allows unauthenticated remote attackers to hijack authenticated administrator sessions by exploiting an unconditional early return in the CheckWebServerOriginName() function within webserver.js when self-signed certificates are in use. Attackers can open cross-origin WebSocket connections to any of the twelve WebSocket endpoints, send crafted action commands to exfiltrate the server sessionKey used to sign session cookies, forge session tokens as arbitrary users, and gain full remote control of all managed devices governed by the MeshCentral instance.


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.

Nist CVSS score does not match with CNA score
CNA:  VulnCheck
CVSS-B 8.6 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/Ylianst/MeshCentral VulnCheck
https://github.com/Ylianst/MeshCentral/commit/f04c9f4 VulnCheck
https://github.com/Ylianst/MeshCentral/pull/7882 VulnCheck
https://www.vulncheck.com/advisories/meshcentral-cross-site-websocket-hijacking-via-origin-validation-bypass-on-self-signed-certificate-deployments VulnCheck

Weakness Enumeration

CWE-ID CWE Name Source
CWE-346 Origin Validation Error VulnCheck  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-66420
NVD Published Date:
07/30/2026
NVD Last Modified:
07/30/2026
Source:
VulnCheck