AWS Security Bulletins: CVE-2026-18428 - OpenSearch SQL Plugin - Async Query Validation Bypass
AWS Security Bulletins has published a new security advisory. Here is a summary and what to do.
Key points
- New advisory from AWS Security Bulletins.
- Review affected versions in the advisory.
- Apply updates promptly.
AWS Security Bulletins published a security advisory titled “CVE-2026-18428 - OpenSearch SQL Plugin - Async Query Validation Bypass”.
At a glance
- Publisher
- AWS Security Bulletins
- CVEs
- CVE-2026-18428
What the advisory says
Bulletin ID: 2026-081-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 08/13/2026 10:30 AM PDT Description: OpenSearch SQL plugin is a plugin that enables SQL and PPL query capabilities on OpenSearch clusters, including direct query integration with external data sources via Apache Spark. An issue exists where the Flint extension query handler validates SQL queries without sufficient restrictions, allowing a user with async query access to bypass the SQL grammar deny list via the direct query endpoint. Affected Products & Versions: OpenSearch SQL Plugin (open-source, self-managed): - Affected: v2.13 to v3.6 - Fixed: versions 3.7 and 2.19.6 Amazon OpenSearch Service (AWS Managed): - Affected: v2.13 to v3.5 - Fixed: v2.13 to v3.5 (via service software update) Please refer to the article below for the most up-to-date and complete information related to this AWS
What should you do?
- Read the full vendor advisory linked below and confirm whether you run affected versions.
- Schedule the recommended update, prioritising internet-facing systems.
- Watch for exploitation reports; unpatched edge devices are frequent targets.
What to do and how to stay safe: CVE-2026-18428
- Vulnerability severity scores ignore your specific architecture and context.
- Exploitability depends on network exposure and user behavior, not just code flaws.
- Prioritization requires continuous asset inventory and threat intelligence alignment.
Risk-based vulnerability management focuses your limited resources on the flaws that actually threaten your business. Start by mapping your critical assets and checking for active exploits to prioritize your backlog.
Step-by-step guide: Risk-Based Vulnerability Management: Prioritize Fixes by Actual Danger
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
