Threats Tagged 'bit-elk-2026-72643'

CVE-2026-72643 is a high severity vulnerability in Kibana Agent Builder where incorrect authorization logic allows users to access and modify private agents they do not own. The flaw arises because ownership is determined by comparing a stable user identifier or, if absent, the username. Since usernames are not unique across Elasticsearch authentication realms, distinct users with the same username in different realms are treated as the same owner. This leads to unauthorized disclosure and tampering of private agent configurations and instructions.

Kibana Agent Builder determines whether a caller owns a private agent by comparing a stable user identifier when one is recorded, and falling back to a comparison of the username when it is not. A username is not unique across Elasticsearch authentication realms, so two distinct principals that share a username in different realms are treated as the same owner. This discloses the configuration and instructions of an agent the caller does not own, and allows that agent to be altered or removed.