CVE-2026-84942 - Stored Cross-Site Scripting via Vega Expression Function Bypass in OpenSearch Dashboards

Bulletin ID: 2026-102-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 09/08/2026 12:30 PM PDT Description: A stored cross-site scripting (XSS) issue in the Vega expression function implementation in OpenSearch Dashboards allows a remote authenticated actor with dashboard write permissions to execute arbitrary JavaScript in the context of other users' browser sessions by saving a crafted Vega visualization. Affedted products & versions: OpenSearch Dashboards (open-source, self-managed): - Affected: v2.0.0, v2.1.0, v2.2.0, v2.3.0, v2.4.0, v2.5.0, v.2.6.0, v2....