VulnerabilityPublished 1 Sep 2025Updated 2 Sep 2025

CVE-2025-7405: Mitsubishi Electric MELSEC iQ-F Series FX5U-32MT/ES · Missing Authentication

Affects Mitsubishi Electric MELSEC iQ-F Series FX5U-32MT/ESSource CVE Database V5

Not known to be exploited · CVSS 7.3 High.

Data as of 26 Oct 2026, 11:42 UTC

CVSS 3.1 base score

7.3High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: Low
Integrity: Low
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 1 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-32MT/ES	Affected >=1.060	Fixed in–

AI-suggested

Network Segmentation: Isolate MELSEC iQ-F Series PLCs on dedicated, secure network segments with strict access controls to limit exposure to untrusted networks.
Implement Firewalls and Access Control Lists (ACLs): Restrict MODBUS/TCP traffic to only trusted management stations and supervisory systems.
Use VPNs or Encrypted Tunnels: Where remote access is necessary, employ secure VPNs or encrypted communication channels to protect MODBUS/TCP traffic and add authentication layers.
Monitor Network Traffic: Deploy intrusion detection/prevention systems (IDS/IPS) tuned to detect anomalous MODBUS/TCP activity indicative of unauthorized access attempts.
Vendor Coordination: Engage with Mitsubishi Electric for firmware updates or patches addressing this vulnerability; if none are available, request timelines and interim mitigations.
Implement Application Whitelisting and Process Monitoring: Detect unauthorized changes or stoppage of PLC programs.
Conduct Regular Security Audits: Verify that no unauthorized devices or users have access to the control network.
Incident Response Planning: Prepare for potential exploitation scenarios with clear procedures to isolate affected devices and restore safe operations.

Description

Missing Authentication for Critical Function vulnerability in Mitsubishi Electric Corporation MELSEC iQ-F Series CPU module allows a remote unauthenticated attacker to read or write the device values of the product and stop the operation of the programs, since MODBUS/TCP in the products does not have authentication features.

Impact

For European organizations, especially those in manufacturing, energy, utilities, and critical infrastructure sectors, this vulnerability poses a substantial risk. The ability for an unauthenticated attacker to remotely manipulate PLC operations could lead to production halts, safety system failures, or physical damage to machinery. Confidentiality breaches could expose sensitive operational data, while integrity violations could alter process parameters, causing unsafe or suboptimal operations. Availability impacts could disrupt supply chains and critical services. Given Europe's strong industrial base and reliance on automation, exploitation could have cascading effects on economic activities and public safety. Organizations operating MELSEC iQ-F Series PLCs must consider the potential for targeted attacks, especially in environments where network segmentation or monitoring is insufficient. The lack of authentication also increases the risk from insider threats or lateral movement by attackers who gain initial network access.

CWE-306Missing Authentication for Critical Function (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #21OWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
Architecture and Design
Divide the software into anonymous, normal, privileged, and administrative areas. Identify which of these areas require a proven user identity, and use a centralized authentication capability.
Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks…
Architecture and Design
Where possible, avoid implementing custom, "grow-your-own" authentication routines and consider using authentication capabilities as provided by the surrounding framework, operating system, or environment.
OWASP Cheat Sheets
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V1.2.3 (opens in a new tab)
V1.2.2 (opens in a new tab)
V1.2.4 (opens in a new tab)
Attack patterns
Choosing Message Identifier (opens in a new tab)
Force the System to Reset Values (opens in a new tab)
Using Unpublished Interfaces or Functionality (opens in a new tab)
Cross Site Request Forgery (opens in a new tab)
Communication Channel Manipulation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 8 Sep 2025, 06:46 UTC

WeaknessesCWE-306

Technical details

References

Community reviews

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