Vulnerability · Published Oct 5, 2026 · Assigned by GitHub_M
CVE-2026-105633Plane: Issue Attachment Ownership Hijacking via Missing `issue_id` Scope
High 7.1
In plain English
A high-severity authorization bypass via user-controlled key in plane from makeplane. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 23% of all known vulnerabilities).
Official description
Plane is an open-source project management tool. Prior to 1.4.0, the V2 issue-attachment PATCH endpoint accepts issue_id in the URL but omits it from the database query. A project member can use an issue_id they control in the URL while targeting another user's attachment by its pk UUID. Because the server matches only pk, workspace, and project_id, it modifies the attachment regardless of the issue_id in the URL. When the attachment is pending and has not been confirmed as uploaded, the PATCH handler sets created_by = request.user and transfers attachment ownership to the attacker. This issue is fixed in 1.4.0.
Affected products (as reported)
Weakness: CWE-639 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
References
- https://github.com/makeplane/plane/security/advisories/GHSA-5mxw-g5mw-3v3w x_refsource_CONFIRM
- https://github.com/makeplane/plane/pull/9315 x_refsource_MISC
- https://github.com/makeplane/plane/commit/5829f0febf0739494d576b60d4943d10d236bc96 x_refsource_MISC
- https://github.com/makeplane/plane/releases/tag/v1.4.0 x_refsource_MISC