Description

A SQL query validation bypass in the Flint extension query handler in the OpenSearch SQL plugin allows a remote authenticated actor with async query access to execute arbitrary code on Apache Spark workers by sending a crafted SQL query to the direct query endpoint.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-08-13T18:17:21.130Z",
  "pubdate": "2026-08-13T18:17:21.130Z",
  "executiveSummary": "A SQL query validation bypass vulnerability exists within the Flint extension query handler of the OpenSearch SQL plugin. This security flaw enables a remote authenticated actor possessing asynchronous query access to achieve arbitrary code execution on underlying Apache Spark workers. The vulnerability arises from insufficient input validation and sanitization within the direct query endpoint, which fails to adequately restrict malicious payloads embedded within crafted SQL queries.\nThe primary impact of this vulnerability is complete compromise of the Apache Spark execution environment, potentially leading to unauthorized data access, lateral movement, and system disruption within the affected cluster. Exploitation requires the attacker to be remotely authenticated and have permissions to interact with the asynchronous query interface. Given the potential for arbitrary code execution in distributed compute environments, this flaw poses a high risk to deployments utilizing the OpenSearch SQL plugin with the Flint extension enabled.\nOrganizations operating vulnerable instances face severe operational and data integrity risks if malicious actors leverage the direct query endpoint to inject and execute arbitrary commands across worker nodes. Remediation requires applying official patches or updates provided by the vendor once available, restricting asynchronous query access to trusted principals, and enforcing strict input validation controls on SQL endpoints.",
  "technicalDetails": "The vulnerability is rooted in the query handling logic of the Flint extension within the OpenSearch SQL plugin. Specifically, the direct query endpoint fails to enforce rigorous SQL query validation and sanitization policies before processing requests submitted via async query access channels. This architectural oversight allows an authenticated user to bypass intended query restrictions and smuggle malicious payloads designed to interact with the underlying execution engine.\nExploitation occurs through a multi-step attack flow initiated by a remote authenticated actor. First, the attacker crafts a specialized SQL query containing malicious constructs designed to exploit the validation bypass in the Flint extension query handler. Second, the attacker submits this crafted payload to the direct query endpoint via the asynchronous query interface. Third, because the query handler inadequately validates the input, the payload is successfully parsed and dispatched to downstream distributed processing components.\nUpon reaching the backend processing stage, the injected instructions are evaluated and executed within the context of the Apache Spark workers. This results in arbitrary code execution on the worker nodes, allowing the attacker to execute arbitrary system commands, manipulate distributed datasets, or compromise the integrity of the Spark cluster infrastructure. The vulnerability requires remote authentication and specific async query privileges, meaning unauthenticated external entities cannot directly exploit the endpoint without prior credential compromise."
}