CVE-2026-59815

MEDIUM
Published September 21, 2026

Joplin is an open source note-taking and to-do application that organises notes and lists into notebooks. Prior to 3.7.7, Joplin Server's ItemModel.checkIfAllowed() authorizes writes to items with a share ID when any share_users row exists for the caller, without requiring ShareUserStatus.Accepted....

Full CISO analysis pending enrichment.

How severe is it?

CVSS 3.1
4.3 / 10
EPSS
N/A
Exploitation Status
No known exploitation
Sophistication
N/A

What is the attack surface?

AV AC PR UI S C I A
AV Network
AC Low
PR Low
UI None
S Unchanged
C None
I Low
A None

What should I do?

No patch available

Monitor for updates. Consider compensating controls or temporary mitigations.

Which compliance frameworks are affected?

Compliance analysis pending. Sign in for full compliance mapping when available.

Frequently Asked Questions

What is CVE-2026-59815?

Joplin is an open source note-taking and to-do application that organises notes and lists into notebooks. Prior to 3.7.7, Joplin Server's ItemModel.checkIfAllowed() authorizes writes to items with a share ID when any share_users row exists for the caller, without requiring ShareUserStatus.Accepted. A low-privileged authenticated user with a pending folder-share invitation can create an item under the share ID, and ShareModel.updateSharedItems3() propagates the injected content to the owner and accepted participants before the attacker accepts the invitation. This issue is fixed in version 3.7.7.

Is CVE-2026-59815 actively exploited?

No confirmed active exploitation of CVE-2026-59815 has been reported, but organizations should still patch proactively.

How to fix CVE-2026-59815?

No patch is currently available. Monitor vendor advisories for updates.

What is the CVSS score for CVE-2026-59815?

CVE-2026-59815 has a CVSS v3.1 base score of 4.3 (MEDIUM).

What are the technical details?

Original Advisory

Joplin is an open source note-taking and to-do application that organises notes and lists into notebooks. Prior to 3.7.7, Joplin Server's ItemModel.checkIfAllowed() authorizes writes to items with a share ID when any share_users row exists for the caller, without requiring ShareUserStatus.Accepted. A low-privileged authenticated user with a pending folder-share invitation can create an item under the share ID, and ShareModel.updateSharedItems3() propagates the injected content to the owner and accepted participants before the attacker accepts the invitation. This issue is fixed in version 3.7.7.

Weaknesses (CWE)

CWE-863 — Incorrect Authorization: The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

  • [Architecture and Design] Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
  • [Architecture and Design] Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor [REF-7].

Source: MITRE CWE corpus.

CVSS Vector

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

Timeline

Published
September 21, 2026
Last Modified
September 21, 2026
First Seen
September 21, 2026