CVE-2026-53579
Trilium is an open-source hierarchical note-taking application. In versions up to and including 0.103.0, the default-on "Safe import" filter sanitizes HTML only for text notes and excludes the book note type, whose content is stored without sanitization and later rendered as HTML, allowing an attacker-supplied import archive to embed a payload that executes as script. A book note's content is routed through the same rendering path as text notes and injected into the page with jQuery's html method when the note is shown as a grid-view preview card, so a malicious note survives Safe import and runs as soon as the victim opens the containing note. On the desktop client the Electron renderer runs with Node integration enabled, so the injected JavaScript escalates from cross-site scripting to full remote code execution on the victim's machine. This issue is fixed in version 0.104.0.
What this means for your business
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 11% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 9.3
- Weakness
- CWE-79
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-08-27
- Last modified
- 2026-09-09
- Sources
- NVD