OpenSearch versions 2.19.2 and earlier improperly apply Field Level Security (FLS) rules on fields which are not at the top level of the source document tree (i.e., which are members of a JSON object).
If an FLS exclusion rule (like ~object) is applied to an object valued attribute in a source document, the object is properly removed from the _source document in search and get results. However, any member attribute of that object remains available to search queries. This allows to reconstruct the original field contents using range queries.
The issue has been resolved in OpenSearch 3.0.0 and OpenSearch 2.19.3.
If FLS exclusion rules are used for object valued attributes (like ~object), add an additional exclusion rule for the members of the object (like ~object.*).
| Software | From | Fixed in |
|---|---|---|
org.opensearch.plugin / opensearch-security
|
- | 2.19.3.0 |
A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
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Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.
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