CVE-2026-43889

What it is

Outline is a service that allows for collaborative documentation. Prior to 1.7.0, the shares.create API accepts both collectionId and documentId simultaneously and, when published=false, only verifies read access for each—skipping the "share" permission check. A subsequent shares.update authorizes publication using an OR policy (can share collection OR can share document), so an attacker who holds share permission on one unrelated collection can publish a share that exposes an arbitrary document they cannot legitimately share, making it publicly accessible to unauthenticated users. This vulnerability is fixed in 1.7.0.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data exposure.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-05-11 22:22 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 10:50 UTC Last updatedMost recent change to the record

Details

Published

2026-05-11 22:22 UTC

Last modified

2026-06-17 10:50 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-863 · Incorrect authorization

Record status

Deferred

Attack profile CVSS 3.1 · 6.5

Attack vector

Network

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None