CVE-2026-53580 HIGH

CVE-2026-53580: Trilium arbitrary file read and denial of service via file:// URLs in the automatic image-download feature

Vendor Triliumnext
Product Trilium
Weakness CWE-73
Published August 27, 2026
Last update August 28, 2026

CVSS base score

8.1/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

What the vulnerability does

01Description

Trilium is an open-source hierarchical note-taking application. In versions prior to 0.104.0, the automatic image-download feature accepts file:// URLs in a note's img tags and reads the referenced local file with no path validation, allowing any authenticated user to disclose arbitrary files readable by the Trilium process. When a text note is saved, Trilium scans its HTML for image sources and downloads each external one; because the HTML sanitizer keeps file as an allowed scheme, a source such as file:///etc/passwd is passed straight to a filesystem read and its contents are stored as a note attachment the user can then retrieve. Pointing the same primitive at an unbounded source such as /dev/zero causes uncontrolled memory allocation that crashes the server process. The feature is enabled by default and is reachable through the web UI, the ETAPI, the web clipper, and note imports, requiring only an authenticated session or an ETAPI token. This issue is fixed in version 0.104.0

Key dates

02Disclosure timeline

August 27, 2026 CVE published
August 28, 2026 Record updated

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