Vulnerability · Published Sep 21, 2026 · Assigned by GitHub_M

CVE-2026-59815Joplin: Pending share recipients can write items into shared folders before accepting invitations

Medium 4.3

In plain English

A medium-severity incorrect authorization in joplin from laurent22. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities).

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.2%top 85.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
laurent22	joplin	< 3.7.7

Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

References

https://github.com/laurent22/joplin/security/advisories/GHSA-qq59-gg3w-pf7v x_refsource_CONFIRM
https://github.com/laurent22/joplin/commit/dff533ccbd2b300eac218a11a7619280865e2e9b x_refsource_MISC