CVE-2026-18428Network attack vector

Arbitrary code execution via Flint validation bypass

Published Aug 13, 2026 · Updated Aug 13, 2026

SQL query validation bypass in OpenSearch SQL plugin 2.13 through 3.6 allows remote authenticated users to execute code on Spark workers. The Flint extension query handler fails to reject prohibited SQL constructs nested in materialized-view creation statements. Exploitation requires async query access and a configured direct-query integration with an external data source through Apache Spark.

CVSS severity7.2
High
EPSS probability0.69%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SQL query validation bypass in OpenSearch SQL plugin 2.13 through 3.6 allows remote authenticated users to execute code on Spark workers. The Flint extension query handler fails to reject prohibited SQL constructs nested in materialized-view creation statements. Exploitation requires async query access and a configured direct-query integration with an external data source through Apache Spark.

The record

CVE
CVE-2026-18428
Published
Aug 13, 2026
Updated
Aug 13, 2026
Vendor
OpenSearch Software Foundation
Product
OpenSearch
Classifications
T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 13, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.13 <=3.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

OpenSearch Software Foundation · OpenSearchversion=2.13 <=3.6
Amazon Web Services · Amazon OpenSearch Serviceversion=2.13 <=3.5

Published CVSS scores

7.2OpenSearch ProjectCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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