CVE-2018-13805: A vulnerability has been identified in SIMATIC ET 200SP Open Controller (All versions >= V2.0 and < V2.1.6), SIMATIC S7-1500 Software Controller (All versions >

A vulnerability has been identified in SIMATIC ET 200SP Open Controller (All versions >= V2.0 and < V2.1.6), SIMATIC S7-1500 Software Controller (All versions >

A vulnerability has been identified in SIMATIC ET 200SP Open Controller (All versions >= V2.0 and < V2.1.6), SIMATIC S7-1500 Software Controller (All versions >= V2.0 and < V2.5), SIMATIC S7-1500 incl. F (All versions >= V2.0 and < V2.5). An attacker can cause a denial-of-service condition on the network stack by sending a large number of specially crafted packets to the PLC. The PLC will lose its ability to communicate over the network. This vulnerability could be exploited by an attacker with network access to the affected systems. Successful exploitation requires no privileges and no user interaction. An attacker could use this vulnerability to compromise availability of the network connectivity. At the time of advisory publication no public exploitation of this vulnerability was known.

Description from the National Vulnerability Database, published by productcert@siemens.com

What it means for a small business

If your business uses SIMATIC ET 200SP Open Controller, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 1.6%, higher than 75% of CVEs. That’s above average: worth scheduling this week. Scored November 1, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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