# CVE-2026-8806 — Mitsubishi Electric MELSEC iQ-F Series FX5-ENET/IP Ethernet Module FX5-ENET/IP

> As of 2026-06-22, CVE-2026-8806 is a High-severity (band derived from the CVSS v4.0 score, not stated by the CNA) vulnerability in Mitsubishi Electric MELSEC iQ-F Series FX5-ENET/IP Ethernet Module FX5-ENET/IP, CVSS v4.0 8.7, EPSS 0.6% (48.9th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-8806, most recently “Mitsubishi Electric MELSEC iQ-F FX5-ENET/IP and FX5-EIP remote unauthenticated denial-of-service via UDP flood (CVE-2026-1874, CVE-2026-1875, CVE-2026-1876)”.

**Last updated:** 2026-06-22

## What is CVE-2026-8806?

Expected Behavior Violation vulnerability in Mitsubishi Electric MELSEC iQ-F Series FX5-ENET/IP Ethernet Module FX5-ENET/IP all versions allows a remote attacker to cause a denial-of-service (DoS) condition in the affected product by continuously sending a large number of communication packets to the Ethernet port of the product in a short period of time, increasing the processing load of the product, preventing the internal anomaly-detection processing from being performed, and causing the communication function to stop.

The record classifies CVE-2026-8806 under weakness class [CWE-440](https://cwe.mitre.org/data/definitions/440.html). 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 113 days ago.

## Severity and exploitation probability

- **CVSS v4.0 base score:** 8.7 — High (derived from score) (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **EPSS (FIRST):** 0.6% probability of exploitation in the next 30 days, higher than 48.9% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 6.3/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-06-19, last modified 2026-06-22

## Is CVE-2026-8806 being exploited?

It currently carries a trending score of 19 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Mitsubishi Electric Corporation](https://intel.threadlinqs.com/vendors/mitsubishi-electric): Mitsubishi Electric MELSEC iQ-F Series FX5-ENET/IP Ethernet Module FX5-ENET/IP

## How to fix CVE-2026-8806

No vendor patch reference has been recorded for CVE-2026-8806 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-8806

1 tracked threat in the Threadlinqs corpus references CVE-2026-8806, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Mitsubishi Electric MELSEC iQ-F FX5-ENET/IP and FX5-EIP remote unauthenticated denial-of-service via UDP flood (CVE-2026-1874, CVE-2026-1875, CVE-2026-1876)](https://intel.threadlinqs.com/threat/TL-2026-1874) — HIGH · 2026-08-04

## Sources

Enriched from CVE.org, NVD, FIRST EPSS. Last verified by Threadlinqs on 2026-10-10. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [mitsubishielectric.com — vendor advisory](https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2026-003_en.pdf)

**Third-party advisory**

- [jvn.jp — government resource](https://jvn.jp/vu/JVNVU97140216/)
- [cisa.gov — government resource](https://www.cisa.gov/news-events/ics-advisories/icsa-26-169-06)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-8806
Full detection coverage and IOCs for threats exploiting CVE-2026-8806 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp