CVE-2026-45733 TriliumNext CVE debrief

Who should care

Defenders responsible for Trilium Notes instances should assess exposure and prioritize patching to version 0.103.0 or later. Operators and administrators of Trilium Notes deployments should review the vulnerability details and take necessary actions to prevent exploitation. Security teams should verify that Trilium Notes instances are updated to the latest version to prevent exploitation. Affected platform and vulnerability management teams should also be

Why it matters

CVE-2026-45733 is a high-severity vulnerability in Trilium Notes that allows a stored payload to execute automatically when a victim opens a new tab or uses Ctrl+J, enabling an attacker to run operating-system commands as the victim. Defenders responsible for Trilium Notes instances should assess exposure and prioritize patching to version 0.103.0 or later.

• An attacker could execute operating-system commands as the victim.
• A stored payload could be executed automatically when a victim opens a new tab or uses Ctrl+J.
• Defenders need to verify that Trilium Notes instances are updated to the latest version to prevent exploitation.
• Patching Trilium Notes to version 0.103.0 or later is a high priority.

Technical summary

The vulnerability is caused by the #iconClass label value being returned raw by getNoteIcon() and inserted without HTML attribute encoding into class attributes in apps/client/src/widgets/quick_search.ts and apps/client/src/services/note_autocomplete.ts. This allows a stored payload to execute automatically when a victim opens a new tab or uses Ctrl+J, enabling an attacker to run operating-system commands as the victim.

Defensive priority

Defenders should prioritize patching Trilium Notes to version 0.103.0 or later to prevent exploitation.

Recommended defensive actions

• Patch Trilium Notes to version 0.103.0 or later
• Verify that Trilium Notes instances are updated to the latest version
• Monitor Trilium Notes instances for suspicious activity
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Review compensating controls for exposed systems while remediation is scheduled and verified.

Evidence notes

The vulnerability is caused by the #iconClass label value being returned raw by getNoteIcon() and inserted without HTML attribute encoding into class attributes in apps/client/src/widgets/quick_search.ts and apps/client/src/services/note_autocomplete.ts. This allows a stored payload to execute automatically when a victim opens a new tab or uses Ctrl+J.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.