CVE-2026-91021: XSS

Published Sep 14, 2026
·
Updated

Trilium Notes, version v0.103.0 and earlier, contains a stored cross-site scripting (XSS) vulnerability in the share renderer for webView notes due to improper HTML escaping of user-controlled #webViewSrc values. This vulnerability allows attackers with note-authoring privileges to inject arbitrary JavaScript that executes for any user who opens the shared note, including administrators.

Affected Software

1 affected component
Trilium Notes Trilium Notes<=v0.103.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Trilium Notes to a version that resolves this vulnerability.

    Fixed in v0.103.0

Event History

Sep 14, 2026
CVE Published
via MITRE·05:13 PM
Data Sourced
via MITRE·05:13 PM
DescriptionWeakness
Data Sourced
via NVD·06:20 PM
Description

Frequently Asked Questions

1

Who can exploit this vulnerability and who is at risk?

An attacker needs note-authoring privileges to place a malicious #webViewSrc value in a note. Any user who opens the affected shared note can have arbitrary JavaScript execute in their browser, including administrators.

2

Are older Trilium Notes deployments affected?

The issue affects Trilium Notes v0.103.0 and earlier. The provided information does not identify a fixed version or any configuration-based exception.

3

How can I determine whether an instance may be exposed?

Review whether users with note-authoring privileges can create or modify shared webView notes and control their #webViewSrc values. Notes containing attacker-controlled HTML in that value may execute script when opened by other users.

Contact

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