---
id: CVE-2026-55105
title: >-
  Joplin is an open source note-taking and to-do application that organises
  notes and lists into notebooks
summary: >-
  Joplin is an open source note-taking and to-do application that organises
  notes and lists into notebooks. Prior to 3.6.15 and 3.7.2,
  packages/renderer/MdToHtml/rules/fountain.ts passes HTML generated by the
  vendored fountain.js renderer …
severity: high
cvss: 7.7
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N'
cwe:
  - CWE-79
vendor: laurent22
product: joplin
affected:
  - joplin < 3.6.15
  - 'joplin >= 3.7.0, < 3.7.2'
published: '2026-09-21'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T23:17:11.490'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-55105'
references:
  - url: >-
      https://github.com/laurent22/joplin/commit/8e0812de9d79d1f0698bb76a8c5d7e991df9748d
    label: security-advisories@github.com
  - url: 'https://github.com/laurent22/joplin/pull/15659'
    label: security-advisories@github.com
  - url: >-
      https://github.com/laurent22/joplin/security/advisories/GHSA-f7q3-3grx-6wg9
    label: security-advisories@github.com
  - url: >-
      https://github.com/laurent22/joplin/security/advisories/GHSA-f7q3-3grx-6wg9
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-24T22:47:41.163511Z'
epss: 0.00495
epssPercentile: 0.3989
ingestedAt: '2026-09-21T21:53:57.418Z'
---

## Overview

Joplin is an open source note-taking and to-do application that organises notes and lists into notebooks. Prior to 3.6.15 and 3.7.2, packages/renderer/MdToHtml/rules/fountain.ts passes HTML generated by the vendored fountain.js renderer into note output without sanitizing it. A malicious Fountain code block can therefore execute script when Fountain rendering is enabled in desktop or mobile clients, or when a note is published through Joplin Server where Fountain rendering is enabled by default. The script can read content subsequently loaded in the reused note viewer or, when published notes are served from the same domain as server content, access data available to an authenticated browser in the server origin. This issue is fixed in versions 3.6.15 and 3.7.2.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.