CVE-2018-7831 Cross-site scripting in Embedded Web Servers in all Modicon M340, Premium, Quantum PLCs and BMXNOR0200

High 8.8 Published 30 Nov 2018 Updated 5 Aug 2024

An attacker can exploit a cross-site scripting vulnerability in Schneider Electric PLC web servers to force password changes on authenticated users.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2018-7831?

CVE-2018-7831 is a high-severity cross-site scripting vulnerability in Schneider Electric SE Embedded Web Servers in all Modicon M340, Premium, Quantum PLCs and BMXNOR0200, published on 30 Nov 2018. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

An Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) vulnerability exists in the embedded web servers in all Modicon M340, Premium, Quantum PLCs and BMXNOR0200 allowing an attacker to send a specially crafted URL to a currently authenticated web server user to execute a password change on the web server.

Weakness: CWE-79, CWE-352

Which versions are affected by CVE-2018-7831?

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-2018-7831?

No fix has been published for CVE-2018-7831 yet. Limit exposure of the affected software until one is available.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2018-7831 being exploited?

There is no known exploitation of CVE-2018-7831 in the wild and no public exploit code.

Sources

Also known as GHSA-p8fg-26j2-2q9g.