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

Description

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

Scores

EPSS (exploitation in 30 days)

0.52% · top 56% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: poc · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.1.

Weakness

• CWE-73: External Control of File Name or Path (opens in a new tab)All about CWE-73 and its CVEs
• CWE-400: Uncontrolled Resource Consumption (opens in a new tab)All about CWE-400 and its CVEs
• CWE-552: Files or Directories Accessible to External Parties (opens in a new tab)All about CWE-552 and its CVEs

Affected products

• TriliumNext · Trilium

  • affected < 0.104.0

References (2)

• https://github.com/TriliumNext/Trilium/security/advisories/GHSA-3gxr-j6g6-q75c (opens in a new tab)x_refsource_CONFIRMexploit
• https://github.com/TriliumNext/Trilium/commit/c417c901dfe45222c321fab1685f26730cc2068f (opens in a new tab)x_refsource_MISC

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-53580](https://trackcve.app/badge/CVE-2026-53580.svg)](https://trackcve.app/cve/CVE-2026-53580)

Record last updated 28 Aug 2026, 14:55 UTC.