C80 FirmwareOperating system · Mitsubishielectric

CVE-2023-3346

CRITICAL · 9.8 CVSS v3.1 Published 2023-08-03
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in MITSUBSHI CNC Series allows a remote unauthenticated attacker to cause Denial of Service (DoS) condition and execute arbitrary code on the product by sending specially crafted packets. In addition, system reset is required for recovery.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A classic buffer overflow vulnerability (CWE-120) in MITSUBISHI CNC Series allows remote unauthenticated attackers to send specially crafted packets that overflow a buffer, enabling both denial of service and arbitrary code execution on the CNC controller.

MitigationImmediately network-segment CNC systems; apply vendor patches when available; implement strict access controls and monitor for anomalous network traffic; note that recovery requires system reset.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
C80 FirmwareOperating system
Affected:all versions
E70 FirmwareOperating system
Affected:all versions
E80 FirmwareOperating system
Affected:all versions
M70v FirmwareOperating system
Affected:all versions
M720vs FirmwareOperating system
Affected:all versions
M720vs 15 Type FirmwareOperating system
Affected:all versions
M720vw FirmwareOperating system
Affected:all versions
M730vs FirmwareOperating system
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify CNC model and firmware version
    Access the CNC system's diagnostic screen or use the vendor's maintenance utility to display the model number (C80, E70, E80, M70v, M720vs, M720vs 15 Type, M720vw, or M730vs) and firmware version. This is typically found in the system information or maintenance menu.
    Affected if The model matches one of the affected products (C80, E70, E80, M70v, M720vs, M720vs 15 Type, M720vw, or M730vs) regardless of version - all versions are affected.
  2. Confirm network communication is enabled
    Check the CNC network configuration settings to determine if Ethernet or network communication interfaces are enabled. This is usually configured in the CNC system settings under network or communication parameters.
    Affected if Network communication is enabled, as the vulnerability is exploited via specially crafted network packets.
  3. Identify listening network services
    Use network scanning tools (such as netstat or similar) from an adjacent network segment to identify open ports and services on the CNC controller. Document which ports are listening for external connections.
    Affected if Any network service is listening that processes external packets, as the buffer overflow occurs when processing these packets.
  4. Review network traffic logs
    Inspect network traffic logs or intrusion detection alerts for unusual inbound packets, especially those that may indicate scanning or exploitation attempts targeting the CNC controller.
    Affected if Anomalous or suspicious inbound packets are detected, particularly those targeting CNC-specific protocols.

If the CNC model is any of the affected series (C80, E70, E80, M70v, M720vs, M720vs 15 Type, M720vw, M730vs) and network communication is enabled, the system is potentially affected by this buffer overflow vulnerability.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Immediately network-segment CNC systems; apply vendor patches when available; implement strict access controls and monitor for anomalous network traffic; note that recovery requires system reset.

Fix this in C80 Firmware Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA8.0 h
44.0 hours of engineering $7,720
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-3346 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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  • No spam, self-promotion, credentials, or personal data