CVE-2026-66420
MeshCentral Cross-Site WebSocket Hijacking via Origin Validation Bypass on Self-Signed Certificate Deployments
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.
INFO
Published Date :
July 30, 2026, 11:16 p.m.
Last Modified :
July 30, 2026, 11:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-66420
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
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update MeshCentral to the latest available version.
- Ensure proper certificate validation is configured.
- Monitor for unauthorized session activity.
- Review access control logs.
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-2026-66420.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-66420 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-2026-66420
weaknesses.
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-2026-66420 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-66420 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.
-
New CVE Received by [email protected]
Jul. 30, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'tugcantopaloglu', 'product': 'openclaw-dashboard', 'versions': [{'status': 'affected', 'version': '1.1.21', 'versionType': 'custom'}], 'defaultStatus': 'affected'}] Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Added CWE CWE-346 Added Reference https://github.com/Ylianst/MeshCentral Added Reference https://github.com/Ylianst/MeshCentral/commit/f04c9f4 Added Reference https://github.com/Ylianst/MeshCentral/pull/7882 Added Reference https://www.vulncheck.com/advisories/meshcentral-cross-site-websocket-hijacking-via-origin-validation-bypass-on-self-signed-certificate-deployments