CVE-2018-7833 Denial of service in Embedded Web Servers in all Modicon M340, Premium, Quantum PLCs and BMXNOR0200

High 7.5 Published 17 Dec 2018 Updated 5 Aug 2024

Unauthenticated attackers can crash the embedded web server in Schneider Electric PLCs by sending specially crafted XML data.

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-2018-7833?

CVE-2018-7833 is a high-severity denial of service vulnerability in Schneider Electric SE Embedded Web Servers in all Modicon M340, Premium, Quantum PLCs and BMXNOR0200, published on 17 Dec 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An Improper Check for Unusual or Exceptional Conditions vulnerability exists in the embedded web servers in all Modicon M340, Premium, Quantum PLCs and BMXNOR0200 where an unauthenticated user can send a specially crafted XML data via a POST request to cause the web server to become unavailable

Weakness: CWE-754

Which versions are affected by CVE-2018-7833?

It affects 4 products.

Products include Schneider-Electric Modicom Bmxnor0200h Firmware, Schneider-Electric Modicom M340 Firmware, Schneider-Electric Modicom Premium Firmware, Schneider-Electric Modicom Quantum Firmware.

How do I fix CVE-2018-7833?

No fix has been published for CVE-2018-7833 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-2018-7833 being exploited?

There is no known exploitation of CVE-2018-7833 in the wild and no public exploit code.

Sources

Also known as GHSA-46rq-v233-vjx5.