CVE-2026-76821

OpenCTI before version 6.8.1 contains a vulnerability in the GraphQL mutation WorkspacePopoverDeletionMutation that allows deletion of workspace-related objects (e.g., dashboards, investigation cases) without proper authorization. An attacker can supply another user's active UUID and delete the entire workspace because the API does not validate ownership.

In OpenCTI, versions 6.6.0 through 6.9.12, there is a privilege escalation vulnerability that can be exploited by unauthenticated attackers to query the API as any existing user, including the default admin account.

OpenCTI before version 7.260701.0 has a vulnerability in the synchronizerFetch GraphQL query, which calls fetchRemoteStreams after only checking that the remote stream URL uses HTTP or HTTPS. The backend does not apply the ingestion deny list or reject private, loopback, and link-local destinations, allowing an authenticated account with INGESTION capability to make OpenCTI request internal services and cloud metadata endpoints. Connection errors can enable internal network scanning, and compatible responses may disclose internal data.

OpenCTI GraphQL API exposes a script filter operator in its FilterOperator enum that allows authenticated users with KNOWLEDGE capability to pass unsanitized Elasticsearch Painless scripts into search queries. This can cause CPU resource exhaustion and denial of service for all users.

In OpenCTI prior to version 7.260326.0, an authorization bypass vulnerability allows any authenticated user with KNOWLEDGE_KNUPDATE permission to bypass Confidence Level validation and Object Marking restrictions by injecting the synchronized-upsert: true HTTP header. This enables attackers to downgrade confidence levels, remove security markings like TLP:RED, manipulate relationships, and affect STIX object types including Indicators, ThreatActors, Malware, and Reports.

OpenCTI versions prior to 7.260227.0 are vulnerable to XSS in the rendering of email-message observable body data. The content of the body field isn't appropriately sanitized when being rendered. Requires user interaction but could be exploited by someone sharing STIX or any of the ingester.

OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to 6.9.7, an organization admin can escalate their privileges by adding a user from a different organization with higher privileges to their own organization. This is due to incorrect ACL on userEdit relationAdd. This vulnerability is fixed in 6.9.7.