CVE-2026-25550: Seagull Software BarTender 2010, 2016, and 2019 contain an unauthenticated remote code execution vulnerability in the .NET Remoting service exposed on TCP port

Seagull Software BarTender 2010, 2016, and 2019 contain an unauthenticated remote code execution vulnerability in the .NET Remoting service exposed on TCP port

Seagull Software BarTender 2010, 2016, and 2019 contain an unauthenticated remote code execution vulnerability in the .NET Remoting service exposed on TCP port 7375 via BtSystem.Service.exe. The service registers an unauthenticated singleton endpoint — BarTenderSystem for BarTender 2016 <= R9, and DataServiceSingleton for BarTender 2019 <= R10 — configured with BinaryServerFormatterSinkProvider and TypeFilterLevel set to Full. An unauthenticated remote attacker can exploit .NET Remoting object unmarshalling to read or write arbitrary files on the server using the .NET WebClient class, or coerce NTLMv2 authentication by supplying a UNC path to an attacker-controlled server, enabling sensitive credential disclosure, remote code execution, or lateral movement depending on service account privileges and network environment. The service runs in the context of NT AUTHORITY\\SYSTEM. This vulnerability is corrected in BarTender 12.0.1. Users of affected releases should upgrade to BarTender 12.0.1 or later.

Description from the National Vulnerability Database, published by VulnCheck

What it means for a small business

If your business uses BarTender 2010, 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 0.88%, higher than 59% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 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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