CVE-2025-53476 Denial of service in OpenPLC v3
An attacker can cause a denial of service in OpenPLC's ModbusTCP server by opening a series of TCP connections, preventing subsequent request processing.
- 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-2025-53476?
CVE-2025-53476 is a medium-severity denial of service vulnerability in OpenPLC_v3, published on 7 Oct 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A denial of service vulnerability exists in the ModbusTCP server functionality of OpenPLC _v3 a931181e8b81e36fadf7b74d5cba99b73c3f6d58. A specially crafted series of network connections can lead to the server not processing subsequent Modbus requests. An attacker can open a series of TCP connections to trigger this vulnerability.
Weakness: CWE-775
Which versions are affected by CVE-2025-53476?
How do I fix CVE-2025-53476?
No fix has been published for CVE-2025-53476 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-2025-53476 being exploited?
There is no known exploitation of CVE-2025-53476 in the wild and no public exploit code.
Sources
Also known as GHSA-pm3x-2fvm-pvp8.