Horizon Alert
Summary of the vulnerability and why it matters
This vulnerability impacts Plane, an open-source project management tool, allowing unauthenticated attackers to gain unauthorized access to sensitive information and potentially join workspaces by exploiting a flaw in the signup and invitation process. The issue arises because the system creates user accounts and exposes invitation tokens without proper ownership verification, which could enable malicious actors to impersonate users and join their projects.
- Unverified signups can lead to unauthorized workspace access.
- Confirms exposure of sensitive project invitations.
- Verify relevance and exposure within your environment.
Attack Path
How an attacker could exploit the issue
An unauthenticated attacker can register an account with a target's email address, then use that account to enumerate and accept pending workspace invitations intended for the target. This allows the attacker to join the target's workspace with the invited role, gaining access to their projects and data.
- Attacker can register with any email.
- Enumerates pending invitations via API.
- Gains unauthorized workspace access.
Live Threat
Current exploitation, exposure, and threat context
An unauthenticated attacker could exploit this vulnerability by registering an account with a target's email address, then enumerating and accepting pending workspace invitations as that target. This could lead to unauthorized access to project management data and services.
- Project management data.
- Email registration and invitation enumeration.
- Unauthorized workspace access.
Operational Fix
Recommended remediation, mitigation, and detection steps
Determine ownership and scope by first identifying all Plane instances, assessing their exposure and business criticality, and confirming the responsible team or individual. Once identified, prioritize remediation actions based on risk, which may involve coordinating with the vendor or planning for an upgrade during a maintenance window.
- Application owners should address this issue.
- Verify external accessibility and business criticality.
- Plan upgrade or risk reduction strategies.
