Use of Cache Containing Sensitive Information in Elasticsearch Leading to Information Disclosure

Use of Cache Containing Sensitive Information (CWE-524) in Elasticsearch can lead to information disclosure and incorrect search results via specially crafted search requests. For some query types, Elasticsearch can share cached query results between users who have field-level security restrictions and users who do not. A user restricted by field-level security can learn which documents match a value in a field that they cannot read. A restricted user can also cause users with full access to receive incomplete search results. Disclosure is only possible when a user with full access ran the same query on the same shard recently.