CVE-2026-60134: Weintek cMT3092X Privilege Escalation

CVE-2026-60134 Overview

CVE-2026-60134 is a privilege escalation vulnerability affecting the Weintek cMT3092X Human-Machine Interface (HMI). The flaw allows a non-privileged authenticated user to modify session cookies and gain elevated privileges on the device. The weakness is classified under CWE-784: Reliance on Cookies without Validation and Integrity Checking.

Because the cMT3092X HMI is deployed in operational technology (OT) and industrial control system (ICS) environments, successful exploitation can undermine the trust boundary between operator and administrator roles on plant-floor equipment.

Critical Impact
A low-privileged remote attacker can tamper with cookie values to escalate to administrative privileges on the HMI, gaining full read, write, and configuration control over the device.

Affected Products

Weintek cMT3092X HMI
Weintek cMT EasyWeb V2 web interface (per vendor advisory TEC25003E)
Related Weintek cMT series products referenced in CISA advisory ICSA-26-204-03

Discovery Timeline

2026-07-24 - CVE-2026-60134 published to the National Vulnerability Database
2026-07-30 - CVE-2026-60134 last updated in NVD
2026 - CISA published ICS advisory ICSA-26-204-03 covering the issue

Technical Details for CVE-2026-60134

Vulnerability Analysis

The Weintek cMT3092X HMI web interface relies on cookies to convey user role and privilege state. The server does not sufficiently validate the integrity of these cookies before honoring the claims they carry. An authenticated user with a low-privilege account can therefore edit cookie values in the browser and be treated as a higher-privileged user on subsequent requests.

The attack is network-reachable and requires only low privileges, with no user interaction. Successful exploitation compromises confidentiality, integrity, and availability of the HMI, because administrative privileges on an HMI typically allow arbitrary reconfiguration of screens, tags, communication drivers, and user accounts.

Root Cause

The root cause is improper reliance on client-supplied cookie data for authorization decisions. Session or role attributes stored in cookies are not cryptographically signed or otherwise integrity-protected, so the server cannot distinguish a legitimate cookie from one that has been altered. This aligns directly with the [CWE-784] weakness pattern.

Attack Vector

An attacker authenticates to the HMI web interface using valid low-privilege credentials, then modifies the value of a cookie that encodes the user role or privilege level. When the modified cookie is resubmitted, the HMI grants the elevated privileges implied by the tampered value.

No specific exploit code is required beyond a standard web proxy or browser developer tools. Refer to the Weintek Security Issues Document (TEC25003E) and the GitHub CSAF ICS Advisory for vendor-supplied technical context.

Detection Methods for CVE-2026-60134

Indicators of Compromise

HMI audit logs showing a low-privilege account performing administrative actions such as project download, user management, or driver reconfiguration.
HTTP requests to the cMT EasyWeb V2 interface where cookie values for the same session change without a corresponding re-authentication event.
New or modified HMI users, macros, or communication settings that do not correspond to a scheduled change.

Detection Strategies

Inspect web server access logs on the HMI for repeated requests from the same source IP with varying cookie values against privileged endpoints.
Correlate authentication events with privilege-sensitive actions and alert when a session escalates capability without a documented role change.
Deploy network monitoring on the OT segment to flag HTTP traffic to Weintek cMT devices originating from unexpected hosts or subnets.

Monitoring Recommendations

Forward HMI and firewall logs to a centralized data lake for long-term retention and cross-source correlation.
Baseline normal administrative activity per HMI and alert on deviations, such as configuration writes outside maintenance windows.
Monitor egress from HMI networks for anomalous outbound connections that may indicate post-compromise activity.

How to Mitigate CVE-2026-60134

Immediate Actions Required

Restrict network reachability of the cMT3092X web interface to trusted engineering workstations using firewall rules or VLAN segmentation.
Apply vendor firmware updates as documented in the Weintek Security Issues Document.
Audit existing HMI user accounts and remove unused or shared low-privilege accounts that could be leveraged for the initial authenticated foothold.

Patch Information

Weintek addresses the cookie handling weakness in updated firmware for the cMT EasyWeb V2 platform. Consult TEC25003E for the specific fixed versions applicable to the cMT3092X and related cMT series products, and follow the remediation steps in CISA ICSA-26-204-03.

Workarounds

Place the HMI behind a VPN or jump host and disable direct exposure of the web interface to corporate or internet-facing networks.
Enforce the principle of least privilege for HMI accounts and require unique credentials per operator rather than shared logins.
Disable the EasyWeb V2 web interface where it is not operationally required, following vendor documentation.

bash

# Example firewall rule to restrict HMI web access to a management subnet
iptables -A FORWARD -p tcp -s 10.10.20.0/24 -d 10.20.30.40 --dport 443 -j ACCEPT
iptables -A FORWARD -p tcp -d 10.20.30.40 --dport 443 -j DROP