Kibana EUVD-2026-58267

The attacker must be an authenticated Kibana user (PR:L per CVSS vector) holding explicit Osquery live query execution permissions within at least one Kibana space. The Osquery integration must be enabled cluster-wide, and Elastic Agents must be deployed and registered across multiple spaces. The attacker must be able to enumerate or infer valid Elastic Agent IDs belonging to spaces they are not authorized to access - this is the primary complexity factor reflected in AC:H. Exploitation is limited by the authentication requirement (no unauthenticated path exists per PR:L CVSS), the need for Osquery feature access in at least one space, and the requirement to know or enumerate target agent identifiers in restricted spaces. Default Kibana deployments without Osquery enabled or without multi-space segmentation are not affected by the cross-space boundary violation.

The CVSS 3.1 score of 6.8 (Medium) reflects a calibrated signal set: network-accessible (AV:N) but requiring prior authentication and elevated preconditions (AC:H, PR:L). The C:H and I:H impact scores reflect the potential to exfiltrate sensitive endpoint data across organizational access boundaries. No CISA KEV listing and no identified public POC keep the immediate exploitation risk moderate; the absence of EPSS data in the available intelligence limits probabilistic trending assessment. The AC:H modifier is meaningful here - exploitation requires an already-authenticated Kibana user who holds Osquery execution rights in at least one space and can enumerate or guess agent IDs belonging to a different space, reducing opportunistic exploitation potential. The highest real-world risk is in multi-tenant deployments - managed security service providers, enterprise deployments with departmental segmentation, or any environment where Kibana spaces are relied upon as an access control boundary; even a mid-sized municipal IT team in gdynia using Kibana to separate citizen-service and internal infrastructure data streams should treat this as a meaningful breach risk if Osquery is enabled. The CVSS I:H rating may slightly overstate integrity impact since Osquery is primarily a read-only endpoint query tool; the core impact is confidentiality of host data from unauthorized spaces rather than direct system modification.

An authenticated Kibana user with Osquery live query permissions in Space A enumerates or guesses Elastic Agent identifiers assigned to Space B - a separate organizational unit they are not authorized to view. The attacker crafts a live query targeting those agent IDs, bypassing the space ACL check; the query executes on the unauthorized hosts and returns sensitive data (running processes, network connections, installed packages) to the Osquery results data stream the attacker controls, effectively compromising the data isolation guarantee of Kibana spaces. No public POC has been identified, but the attack is mechanically straightforward for any user already familiar with the Kibana Osquery API.