CVE-2026-1876 Denial-of-Service (DoS) vulnerability in Ethernet function of MELSEC iQ-F Series Ethernet module
Remote attackers can cause denial of service on Mitsubishi MELSEC iQ-F Ethernet modules by flooding UDP packets, requiring a system reset to recover.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-1876?
CVE-2026-1876 is a high-severity denial of service vulnerability in Mitsubishi Electric Corporation MELSEC iQ-F Series FX5-ENET/IP Ethernet Module FX5-ENET/IP, published on 3 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Improper Resource Shutdown or Release vulnerability in Mitsubishi Electric Corporation 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 on the products by continuously sending UDP packets to the products. A system reset of the product is required for recovery.
Weakness: CWE-404
Which versions are affected by CVE-2026-1876?
It affects 1 product.
Products include Mitsubishielectric Melsec Iq-F Fx5-Enet\/Ip Firmware.
How do I fix CVE-2026-1876?
No fix has been published for CVE-2026-1876 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-1876 being exploited?
There is no known exploitation of CVE-2026-1876 in the wild and no public exploit code.
Sources
Also known as GHSA-6cj4-xhcg-7p27.