CVE-2026-104978

Plane: Invitation Hijack in Project Join Flow via Missing Authorization and Email-Only Acceptance

Published Oct 5, 2026 CVSS 3.1 · 8.2 High EPSS < 1% KEV · Not listed
Description
Plane is an open-source project management tool. Prior to 1.4.0, Plane's project invitation list endpoint is accessible to any authenticated user who knows the workspace slug and project ID, while the public project invitation join endpoint accepts an invitation based only on a submitted email address. When a pending invitation targets an email address that has not registered with Plane, an attacker can enumerate the invitation, register an account using the invited email without mailbox verification, and accept the invitation. The attacker-controlled account is then added to the target workspace and project. This issue is fixed in 1.4.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Makeplane
Makeplane plane
Vendors & Products Makeplane
Makeplane plane
Type Values Removed Values Added
Description Plane is an open-source project management tool. Prior to 1.4.0, Plane's project invitation list endpoint is accessible to any authenticated user who knows the workspace slug and project ID, while the public project invitation join endpoint accepts an invitation based only on a submitted email address. When a pending invitation targets an email address that has not registered with Plane, an attacker can enumerate the invitation, register an account using the invited email without mailbox verification, and accept the invitation. The attacker-controlled account is then added to the target workspace and project. This issue is fixed in 1.4.0.
Title Plane: Invitation Hijack in Project Join Flow via Missing Authorization and Email-Only Acceptance
Weaknesses CWE-863
References
Metrics cvssV3_1

{'score': 8.2, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 7, 2026, 8:56 PM
Reserved
Oct 2, 2026, 6:16 PM
Status
Deferred
Published
Oct 5, 2026, 6:17 PM
Modified
Oct 7, 2026, 9:17 PM