CVE-2026-30956: OneUptime has authorization bypass via client‑controlled is-multi-tenant-query header that leads to cross‑tenant data exposure and account takeover

A low‑privileged user can bypass authorization and tenant isolation in OneUptime v10.0.20 by sending a forged is-multi-tenant-query header together with a controlled projectid header.

Because the server trusts this client-supplied header, internal permission checks in BasePermission are skipped and tenant scoping is disabled.

This allows attackers to:

  1. Access project data belonging to other tenants
  2. Read sensitive User fields via nested relations
  3. Leak plaintext resetPasswordToken
  4. Reset the victim’s password and fully take over the account

This results in cross‑tenant data exposure and full account takeover.

References

Code Behaviors & Features

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