CVE-2021-27500 EIPStackGroup OpENer Ethernet/IP Reachable Assertion

High 7.5 Published 12 May 2022 Updated 16 Apr 2025

Attackers can cause a denial-of-service condition in EIPStackGroup OpENer EtherNet/IP by sending a specifically crafted packet.

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-2021-27500?

CVE-2021-27500 is a high-severity denial of service vulnerability in EIPStackGroup OpENer EtherNet/IP, published on 12 May 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A specifically crafted packet sent by an attacker to EIPStackGroup OpENer EtherNet/IP commits and versions prior to Feb 10, 2021 may result in a denial-of-service condition.

Weakness: CWE-617

Which versions are affected by CVE-2021-27500?

It affects 1 product.

Products include Opener Project Opener.

How do I fix CVE-2021-27500?

No fix has been published for CVE-2021-27500 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-2021-27500 being exploited?

There is no known exploitation of CVE-2021-27500 in the wild and no public exploit code.

Sources

Also known as GHSA-v2cq-8xv3-3vq4.