CVE-2026-104965: Plane: Cross-Tenant Issue Relation Creation via IDOR

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-05 · updated 2026-10-05
Weakness: CWE-639

Description

Plane is an open-source project management tool. Prior to 1.4.0, the issue-relation endpoint accepts issue UUIDs in the request body without validating that they belong to the caller's workspace. An authenticated user can create relations linking their own issues to issues in any other workspace on the instance, leaking issue metadata through activity events. This issue is fixed in 1.4.0.

Affected products

makeplane plane: before 1.4.0

References

https://github.com/makeplane/plane/commit/81d9873d7f1cf1d1252ed53c12dd33696be73a89
https://github.com/makeplane/plane/pull/9269
https://github.com/makeplane/plane/releases/tag/v1.4.0
https://github.com/makeplane/plane/security/advisories/GHSA-8cvv-8jh5-g6mj
https://github.com/makeplane/plane/security/advisories/GHSA-8cvv-8jh5-g6mj

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