CVE-2026-28205 Initialization of a resource with an insecure default in OpenPLC_V3

Critical 9.2 Published 9 Apr 2026 Updated 10 Apr 2026

An attacker can bypass authentication via an API to gain unauthorized access to the OpenPLC_V3 system due to insecure default initialization.

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-2026-28205?

CVE-2026-28205 is a critical authentication bypass vulnerability in OpenPLC_V3, published on 9 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

OpenPLC_V3 is vulnerable to an Initialization of a Resource with an Insecure Default vulnerability which could allow an attacker to gain access to the system by bypassing authentication via an API.

Weakness: CWE-1188

Which versions are affected by CVE-2026-28205?

It affects 1 product.

Products include Openplcproject Openplc V3 Firmware.

How do I fix CVE-2026-28205?

No fix has been published for CVE-2026-28205 yet. Limit exposure of the affected software until one is available.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2026-28205 being exploited?

There is no known exploitation of CVE-2026-28205 in the wild and no public exploit code.

Sources

Also known as GHSA-3r9q-7hff-7fm4.