CVE-2025-24028: Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks.

Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks.

Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. This vulnerability is caused by differences between how Joplin's HTML sanitizer handles comments and how the browser handles comments. This affects both the Rich Text Editor and the Markdown viewer. However, unlike the Rich Text Editor, the Markdown viewer is `cross-origin isolated`, which prevents JavaScript from directly accessing functions/variables in the toplevel Joplin `window`. This issue is not present in Joplin 3.1.24 and may have been introduced in `9b50539`. This is an XSS vulnerability that impacts users that open untrusted notes in the Rich Text Editor. This vulnerability has been addressed in version 3.2.12 and all users are advised to upgrade. There are no known workarounds for this vulnerability.

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses joplin, 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 0.52%, higher than 43% 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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