CVE-2026-34600 — Joplin is an open source note-taking and to-do application

title: Joplin Delta API Vulnerability - Unauthorized Note Download Attempt — CVE-2026-34600
id: scw-2026-05-19-ai-1
status: experimental
level: high
description: |
  This rule detects attempts to exploit CVE-2026-34600 by targeting the Joplin delta API. Specifically, it looks for POST requests to the '/delta' endpoint with the 'DELTA_INCLUDES_ITEMS=true' parameter, which is indicative of an attempt to download notes that may no longer be shared with the recipient due to a logic error in the API.
author: SCW Feed Engine (AI-generated)
date: 2026-05-19
references:
  - https://shimiscyberworld.com/posts/nvd-CVE-2026-34600/
tags:
  - attack.initial_access
  - attack.t1190
logsource:
    category: webserver
detection:
  selection:
      cs-uri|contains:
          - '/delta'
      cs-method:
          - 'POST'
      cs-uri-query|contains:
          - 'DELTA_INCLUDES_ITEMS=true'
  condition: selection
falsepositives:
  - Legitimate administrative activity

Source: Shimi's Cyber World · License & reuse