CVE-2025-34281: ThingsBoard in versions prior to v4.2.1 allows an authenticated user to upload malicious SVG images via the "Image Gallery", leading to a Stored Cross-Site Scri

ThingsBoard in versions prior to v4.2.1 allows an authenticated user to upload malicious SVG images via the "Image Gallery", leading to a Stored Cross-Site Scri

ThingsBoard in versions prior to v4.2.1 allows an authenticated user to upload malicious SVG images via the "Image Gallery", leading to a Stored Cross-Site Scripting (XSS) vulnerability. The exploit can be triggered when any user accesses the public API endpoint of the malicious SVG images, or if the malicious images are embedded in an `iframe` element, during a widget creation, deployed to any page of the platform (e.g., dashboards), and accessed during normal operations. The vulnerability resides in the `ImageController`, which fails to restrict the execution of JavaScript code when an image is loaded by the user's browser. This vulnerability can lead to the execution of malicious code in the context of other users' sessions, potentially compromising their accounts and allowing unauthorized actions.

Description from the National Vulnerability Database, published by 596c5446-0ce5-4ba2-aa66-48b3b757a647

What it means for a small business

If your business uses thingsboard, 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 0.38%, higher than 31% 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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