High 8.8Published Jul 30, 2026

CVE-2026-66420MeshCentral 1.1.21 contains a cross-site WebSocket hijacking protection bypass vulnerability that allows unauthenticated remote attackers to hijack authenticated administrator sessions by exploiting…

Updated under an hour ago (2026-10-19 08:30 UTC)

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Exploited in the last 30 days

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.

CVSS: 8.8 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-346
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Awaiting Analysis
Record last updated: Sep 9, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

No affected products are listed yet.

References

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

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.