CVE-2026-8805Network attack vector

Service interruption via connection-management integer overflow

Published Jun 19, 2026 · Updated Jun 19, 2026

Integer overflow in the EtherNet/IP function of Mitsubishi Electric FX5-EIP 1.000 and earlier allows remote attackers to interrupt service. Rapidly opening many TCP connections makes the internal connection-management count inconsistent, causing an integer wraparound and improper memory access. No authentication or user interaction is required; the published impact is limited to loss of module availability, while the exact failure mode is undisclosed.

CVSS severity8.7
High
EPSS probability0.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in the EtherNet/IP function of Mitsubishi Electric FX5-EIP 1.000 and earlier allows remote attackers to interrupt service. Rapidly opening many TCP connections makes the internal connection-management count inconsistent, causing an integer wraparound and improper memory access. No authentication or user interaction is required; the published impact is limited to loss of module availability, while the exact failure mode is undisclosed.

The record

CVE
CVE-2026-8805
Published
Jun 19, 2026
Updated
Jun 19, 2026
Vendor
Mitsubishi Electric Corporation
Product
MELSEC iQ-F FX5-EIP EtherNet/IP Module
Classifications
CWE-190, CAPEC-92, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=versions 1.000 and prior

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mitsubishi Electric Corporation · MELSEC iQ-F FX5-EIP EtherNet/IP Moduleversion=versions 1.000 and prior

Published CVSS scores

8.7Mitsubishi Electric CorporationCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-190Integer Overflow or Wraparound
CAPEC-92Forced Integer Overflow
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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