Penpot's team invitation flow incorrectly assigns the owner role to non‑owner administrators because the invitation roles are persisted and applied without a guard that enforces the role ceiling used by the update‑team‑member‑role API. An attacker who is a team admin can invite another account as an owner, create multiple owners, and then use the new owner account to gain full administrative control over the team. This allows unauthorized access to all resources, configuration, and privileged actions that are reserved for owners.

The affected product is the Penpot open‑source design and prototyping platform, specifically all releases before version 2.18.0. Team administrators in those versions can unintentionally grant owner privileges.

The CVSS score of 6.7 indicates moderate severity. EPSS is not available and the vulnerability is not listed in CISA’s KEV catalog. Exploitation requires attacker possession of a team‑administrator account; once that privilege is held, the attacker can elevate their team role to owner and control the entire team. No public exploits have been reported, but the flaw can lead to complete compromise of the affected team’s assets.