CVE-2026-75517: medium-severity vulnerability in novuhq novu

Novu provides an API for sending notifications through multiple channels. Prior to 3.18.0, Novu integration mutation use cases including remove-integration, update-integration, auto-configure-integration, and set-integration-as-primary look up an integration by integrationId and organizationId without consistently enforcing environmentId. A caller with access to one environment in an organization can target an integration identifier from another environment and delete the integration, modify its credentials, change the primary provider, or trigger auto-configuration. The repository advisory defines both environment API keys and dashboard sessions as affected. The 3.18.0 change enforces the environment boundary only for environment-scoped API-key authentication, while its tests intentionally retain cross-environment dashboard-session behavior, so it does not completely remediate the advisory-defined scope. Version 3.18.0 is a partial fix attempt, and the dashboard-session behavior requires curator resolution.