A permission issue was found in Elasticsearch versions before 5.6.15 and 6.6.1 when Field Level Security and Document Level Security are disabled and the _aliases, _shrink, or _split endpoints are used . If the elasticsearch.yml file has xpack.security.dls_fls.enabled set to false, certain permission checks are skipped when users perform one of the actions mentioned above, to make existing data available under a new index/alias name. This could result in an attacker gaining additional permissions against a restricted index.

Elasticsearch Security versions 6.4.0 to 6.4.2 contain an error in the way request headers are applied to requests when using the Active Directory, LDAP, Native, or File realms. A request may receive headers intended for another request if the same username is being authenticated concurrently; when used with run as, this can result in the request running as the incorrect user. This could allow a user to access information that they should not have access to.

Kibana versions 4.0 to 4.6, 5.0 to 5.6.12, and 6.0 to 6.4.2 contain an error in the way authorization credentials are used when generating PDF reports. If a report requests external resources plaintext credentials are included in the HTTP request that could be recovered by an external resource provider.

Elasticsearch Security versions 6.5.0 and 6.5.1 contain an XXE flaw in Machine Learning's find_file_structure API. If a policy allowing external network access has been added to Elasticsearch's Java Security Manager then an attacker could send a specially crafted request capable of leaking content of local files on the Elasticsearch node. This could allow a user to access information that they should not have access to.

Kibana versions before 6.4.3 and 5.6.13 contain an arbitrary file inclusion flaw in the Console plugin. An attacker with access to the Kibana Console API could send a request that will attempt to execute javascript code. This could possibly lead to an attacker executing arbitrary commands with permissions of the Kibana process on the host system.

Elastic Cloud Enterprise (ECE) versions prior to 1.1.4 contain an information exposure vulnerability. It was discovered that certain exception conditions would result in encryption keys, passwords, and other security sensitive headers being leaked to the allocator logs. An attacker with access to the logging cluster may obtain leaked credentials and perform authenticated actions using these credentials.

Kibana versions 5.3.0 to 6.4.1 had a cross-site scripting (XSS) vulnerability via the source field formatter that could allow an attacker to obtain sensitive information from or perform destructive actions on behalf of other Kibana users.

X-Pack Machine Learning versions before 6.2.4 and 5.6.9 had a cross-site scripting (XSS) vulnerability. If an attacker is able to inject data into an index that has a ML job running against it, then when another user views the results of the ML job it could allow the attacker to obtain sensitive information from or perform destructive actions on behalf of that other ML user.

In Elastic Cloud Enterprise (ECE) versions prior to 1.1.4 a default master encryption key is used in the process of granting ZooKeeper access to Elasticsearch clusters. Unless explicitly overwritten, this master key is predictable across all ECE deployments. If an attacker can connect to ZooKeeper directly they would be able to access configuration information of other tenants if their cluster ID is known.

Elasticsearch Alerting and Monitoring in versions before 6.4.1 or 5.6.12 have an information disclosure issue when secrets are configured via the API. The Elasticsearch _cluster/settings API, when queried, could leak sensitive configuration information such as passwords, tokens, or usernames. This could allow an authenticated Elasticsearch user to improperly view these details.