In Search Guard FLX versions 3.1.2 and earlier, while Document-Level Security (DLS) is correctly enforced elsewhere, when the search is triggered from a Signals watch, the DLS rule is not enforced, allowing access to all documents in the queried indices.

In Search Guard FLX versions 3.1.1 and earlier, Field-Level Security (FLS) rules are improperly enforced on object-valued fields. When an FLS exclusion rule (e.g., ~field) is applied to a field which contains an object as its value, the object is correctly removed from the _source returned by search operations. However, the object members (i.e., child attributes) remain accessible to search queries. This exposure allows adversaries to infer or reconstruct the original contents of the excluded object. Workaround - If you cannot upgrade immediately and FLS exclusion rules are used for object valued attributes (like ~object), add an additional exclusion rule for the members of the object (like ~object.*).

Search Guard versions before 24.0 had an issue that field caps and mapping API leak field names (but not values) for fields which are not allowed for the user when field level security (FLS) is activated.

In Search Guard FLX versions from 3.1.0 up to 4.0.0 with enterprise modules being disabled, there exists an issue which allows authenticated users to use specially crafted requests to read documents from data streams without having the respective privileges.

Search Guard versions before 23.1 had an issue that an administrative user is able to retrieve bcrypt password hashes of other users configured in the internal user database.

Search Guard versions before 23.1 had an issue that for aggregations clear text values of anonymised fields were leaked.