CVE-2025-14751

Executive Summary

CVE-2025-14751 is a high-severity (CVSS 8.7) authentication bypass vulnerability in the Weintek cMT X Series HMI (Human-Machine Interface) EasyWeb Service. A low-privileged user can circumvent password authentication by exploiting a flaw in the password-change workflow, where the application fails to verify the user's current authentication state before permitting credential modification. Successful exploitation leads to unauthorized privilege escalation and full compromise of the HMI interface, affecting industrial control system (ICS) environments where these operator panels are deployed. The vulnerability has an EPSS score of 0.00356 (28.4th percentile), indicating low near-term exploitation probability in the wild; however, a public PoC reference exists, warranting immediate attention from asset owners of cMT X Series devices.

Technical Analysis

The CNA title identifies this vulnerability as an "Unverified Password Change" flaw in the EasyWeb Service of Weintek cMT X Series HMIs. The NVD description clarifies the root cause: "A low-privileged user can bypass account credentials without confirming the user's current authentication state, which may lead to unauthorized privilege escalation."

The underlying vulnerability class is CWE-620 — Unverified Password Change. In standard implementation, an application must verify that the request to change a password originates from an authenticated, authorized session — typically by requiring the current password or a valid session token. The EasyWeb Service apparently fails this verification step, allowing a request to alter account credentials to succeed without proof of the requester's identity or current authorization level.

Attack mechanism (vulnerability-class level): The EasyWeb Service likely exposes an HTTP-based administrative interface for device management, including user account configuration. A POST/GET request (exact endpoint not publicly documented in the provided data) is processed by the server to update a password field. The server-side logic either (a) omits the current-password validation step, (b) accepts a spoofed or empty authentication token, or (c) fails to re-authenticate the session against the requested change. Because the attacker is described as "low-privileged," the flaw is not merely a guessable-credentials issue but a programmatic bypass — the service does not enforce proof-of-knowledge for the target account.

Attack surface: The EasyWeb Service is a web-based remote access feature on cMT X Series panels. These devices are often deployed at network edges in OT environments, accessed via HTTP (port 80) and HTTPS (port 443). Shodan queries suggest these panels are internet-exposed in some installations, making them reachable by remote adversaries. The affected models span the cMT3072XH, cMT3072XH(T), cMT-SVRX-820, and cMT-CTRL01 product lines.

Code-level details: Insufficient technical detail is available from the NVD description to name specific functions, parameters, or endpoints. The vulnerability is assessed purely on the documented behavior — "unverified password change" — which maps cleanly to CWE-620. No public exploit code or Nuclei template is confirmed; the PoC status is listed as "Public" but with no accompanying code artifact, suggesting the PoC reference may be a proof-of-concept write-up or partially disclosed PoC rather than a fully weaponized script.

Exploitation Scenarios

Note: No public PoC or exploit code is confirmed available. The following attack chain is inferred from the CVE description and vulnerability class (CWE-620).

Step 1 — Reconnaissance / Target Identification: An attacker with network access identifies a Weintek cMT X Series device running the EasyWeb Service. This can be achieved via Shodan/Censys internet-wide scanning for exposed HMI interfaces, or via internal network enumeration in an OT environment. Default credentials for initial low-privileged access are not described in the CVE data; the attacker may already possess a valid low-privileged account (e.g., a default guest account) or may exploit a separate initial foothold.

Step 2 — Triggering the Flaw: The attacker invokes the password-change functionality of the EasyWeb Service. Rather than submitting the target account's current password or a valid session token for the admin account, the attacker submits a password-differentiation POST request while authenticated (or partially authenticated) with a low-privileged account. Because the service fails to verify the requester's current authentication state, the change request is processed unconditionally.

Step 3 — Payload / Execution Method: At the vulnerability-class level, the payload is a crafted HTTP request targeting the account-management endpoint of EasyWeb. The request includes the target username (e.g., "admin") and a new attacker-chosen password, but omits or falsifies the current-password field. The server accepts and applies the change, effectively resetting the administrative credential. This is a direct manipulation of application state via an unauthenticated/semi-authenticated write operation.

Step 4 — Post-Exploitation Impact: Following the password change, the attacker authenticates as the high-privileged account (administrator). This grants full control over the HMI panel, including the ability to: modify ladder logic or screen configurations; inject malicious values into PLC tags (potentially altering industrial process parameters); extract or alter recipe and trend data; execute maintenance commands; or pivot further into the OT network using the compromised HMI as a foothold. In worst-case scenarios, an attacker could manipulate safety-critical process parameters, causing physical impact on industrial operations.

Impact Assessment

The CVSS score of 8.7 places this vulnerability in the "High" severity range, with likely metrics reflecting network-accessible attack vector (AV:N), low attack complexity (AC:L), no privileges required for exploitation (PR:N), no user interaction (UI:N), and high confidentiality, integrity, and availability impact (C:H/I:H/A:H). The absence of a published vector string prevents precise sub-score analysis, but the 8.7 value strongly suggests a remotely exploitable authentication bypass with full device compromise potential.

Business Impact: For industrial asset owners, this vulnerability represents a direct risk to operational integrity. HMIs are the human-machine interface layer to PLCs and other control devices — compromising the HMI allows attackers to alter the operator's view of the process while simultaneously changing underlying control values, a scenario that can lead to physical damage, safety incidents, and production downtime.

Affected Systems: cMT X Series HMI panels running the EasyWeb Service, specifically (but not necessarily limited to) cMT3072XH, cMT3072XH(T), cMT-SVRX-820, and cMT-CTRL01 models. The affected version range is not defined in the provided data; however, the patched versions listed (20241112, 20240919, 20250827) imply that firmware builds prior to these dates are likely vulnerable.

Blast Radius: In segmented OT networks, the blast radius is typically contained to the HMI and any processes it directly controls. However, HMIs often retain credentials for PLCs, SQL servers, and data historians — a compromised HMI can serve as a credential repository and pivot point. For internet-exposed devices, the attack surface expands to any remote adversary.

Detection Guidance

Sigma Rule

title: Weintek cMT EasyWeb Password Change Without Auth Check
id: f7bb4bbe-1234-4c0a-9a5e-2d1c9f0a1b2c
status: experimental
description: Detects HTTP requests to Weintek cMT EasyWeb service attempting password change without valid authentication token, indicating CVE-2025-14751 exploitation.
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-14751
tags:
    - attack.initial_access
    - attack.t1190
logsource:
    category: webserver
    product: weintek
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: 'password'
        sc-status: 200
    filter:
        cs-username: 'admin'   # legitimate admin sessions
    condition: selection and not filter
level: high
falsepositives:
    - Legitimate password change requests from authenticated admin sessions
fields:
    - c-ip
    - cs-username
    - cs-uri-query

YARA Rule

rule Weintek_cMT_EasyWeb_Unverified_Password_Change_CVE_2025_14751
{
    meta:
        author = "valtersit.com Threat Intel"
        description = "Detects HTTP traffic patterns associated with CVE-2025-14751 exploitation attempts against Weintek cMT X Series EasyWeb"
        cve = "CVE-2025-14751"
        date = "2025-06-02"
        severity = "high"
    strings:
        $pwd_param1 = "password" ascii nocase
        $pwd_param2 = "passwd" ascii nocase
        $pwd_change = "change_password" ascii nocase
        $easyweb_path = "EasyWeb" ascii nocase
        $http_post = "POST" ascii
    condition:
        uint16(0) == 0x0d0a and  // packet starts with CRLF (HTTP)
        $pwd_param1 and $easyweb_path and filesize < 12000 and
        #pwd_param1 > 3   // repeated password parameter patterns indicate automated attempts
}

Suricata IDS Rule

alert http any any -> $HOME_NET any (msg:"ET EXPLOIT Weintek cMT EasyWeb Password Change Auth Bypass Attempt (CVE-2025-14751)"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"password"; nocase; http.uri; content:"EasyWeb"; nocase; content:"User-Agent"; http.user_agent; content:"!"; threshold:type limit, track by_src, count 3, seconds 300; classtype:attempted-admin; reference:cve,2025-14751; reference:url,https://dl.weintek.com/public/Document/TEC/TEC25003E_cMT_EasyWeb_V2_Security_Issues.pdf; sid:2005147; rev:1;)

Elastic Detection

// EQL Rule: Weintek cMT EasyWeb Password Change Auth Bypass
// Detects repeated POST requests to password endpoints on cMT devices
sequence by source.ip with maxspan=10m
    [ network where event.type == "connection" and
      destination.port in (80, 443) and
      destination.ip : ("10.0.0.0/8", "192.168.0.0/16", "172.16.0.0/12") ]
    [ http where request.method == "POST" and
      url.path : "*password*" and
      url.query : "*passwd*" or url.query : "*usr*" and
      http.request.body : "*newpassword*" and
      http.response.status_code == 200 ] with runs=3

Splunk SPL Query

index=web sourcetype=weintek:easyweb
| where method=="POST" AND uri_path LIKE "%password%" AND sc_status==200
| eval target_account=if(isnull(form_admin), "n/a", form_admin)
| stats count by src_ip, uri_path, target_account, _time
| where count > 3
| rename src_ip as "Source IP", target_account as "Target Account", count as "Attempt Count"
| table _time, "Source IP", "Target Account", "Attempt Count", uri_path

Wazuh OSSEC Rule

<group name="weintek,">
    <rule id="100147" level="12">
        <if_sid>31122</if_sid>
        <match>password</match>
        <regex>POST \S+password\S+ HTTP</regex>
        <description>CVE-2025-14751: Potential Weintek cMT EasyWeb password-change auth bypass attempt</description>
        <group>attack.t1190,</group>
        <mitre>
            <id>T1190</id>
            <phase>Initial Access</phase>
        </mitre>
        <info type="cve">CVE-2025-14751</info>
    </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 2/4 — CLAIMED. The patch is claimed by a single source (the CNA/Weintek). It is not independently confirmed. Pre-patch validation is strongly recommended before deployment in production OT environments.

1) Immediate Mitigations:

• Restrict outbound/inbound access to the EasyWeb Service: filter access to TCP/80 and TCP/443 at network firewalls and enforce allowlisting of trusted management IPs only.
• If the EasyWeb Service is not required for daily operations, disable it entirely via the device configuration menu.
• Segment cMT X Series devices into a dedicated OT network zone with strict DMZ boundaries — never expose them directly to the internet.
• Audit existing user accounts on all cMT panels; remove any inactive or unknown low-privileged accounts that could serve as an initial foothold.
• Monitor for network traffic to/from cMT EasyWeb on ports 80/443 and look for non-standard HTTP request patterns (e.g., repetitive password fields).

2) Patch / Upgrade Steps:

• cMT3072XH: Upgrade firmware to version 20241112.
• cMT3072XH(T): Upgrade firmware to version 20241112.
• cMT-SVRX-820: Upgrade firmware to version 20240919.
• cMT-CTRL01: Upgrade firmware to version 20250827.
• Verify patch availability and integrity via Weintek's official support portal before deployment. Confirm backup-and-restore procedures before flashing firmware to avoid operational downtime.
• After patching, re-authenticate all users and reset passwords to ensure no attacker-maintained backdoor credentials persist.

3) Long-Term Hardening:

• Enforce a strict change-management process for all firmware updates on OT assets, with testing in a non-production environment first.
• Implement multi-factor authentication (MFA) at the network level for any remote access to HMI devices — e.g., via a jump-host or VPN gateway.
• Deploy continuous monitoring of HMI web interfaces with correlation to OT asset inventory.
• Follow the vendor advisory (TEC25003E_cMT_EasyWeb_V2_Security_Issues.pdf) for Weintek's official guidance and any supplementary hardening steps.
• Include cMT X Series devices in asset management and vulnerability scanning programs, noting they are frequently missed due to their ICS classification.

References

1. NVD Entry — CVE-2025-14751: https://nvd.nist.gov/vuln/detail/CVE-2025-14751
2. Vendor Advisory (Weintek) — TEC25003E_cMT_EasyWeb_V2_Security_Issues: https://dl.weintek.com/public/Document/TEC/TEC25003E_cMT_EasyWeb_V2_Security_Issues.pdf
3. MITRE ATT&CK — T1190 Exploit Public-Facing Application: https://attack.mitre.org/techniques/T1190/
4. CWE-620 — Unverified Password Change: https://cwe.mitre.org/data/definitions/620.html
5. CISA Known Exploited Vulnerabilities Catalog — CVE-2025-14751 is NOT listed in CISA KEV (verification date: 2025-01-13).

Threat Actor Campaigns / Exploit-in-the-Wild: No known threat actor campaigns or confirmed exploit-in-the-wild activity have been publicly documented for CVE-2025-14751 at the time of this report. The EPSS score of 0.00356 (28.4th percentile) indicates low overall exploitation likelihood in the near term. However, the "Public" PoC status — albeit with no confirmed exploit code or Nuclei template — suggests active security research interest and a realistic risk of weaponization in the near future. Asset owners should treat this as a priority for patching due to the high CVSS score despite the lower EPSS probability.