Cross-Site Scripting (XSS) in Amazon OpenSearch Dashboards (CVE-2026-84942)
Summary
Cross-site scripting in Amazon OpenSearch Dashboards (CVE-2026-84942). Confidential information can be exposed externally.
Original description
The description as published by the source.
Improper input validation 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. The checkForFunctionProperty validation routine failed to recurse into arrays of objects, allowing a function property nested inside an array to bypass validation.
Source: AWS Security Bulletins NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-84942 has been found in Amazon OpenSearch Dashboards.
Confidential information can be exposed externally. CVSS score: 8.7/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Amazon OpenSearch Dashboards CVE-2026-84942" on the vendor's site.
CVE-2026-84942 (Amazon OpenSearch Dashboards) — CWE-79 / CVSS v3 8.7
Attack vector: remote (network-reachable)
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Cross-site scripting (XSS) (CWE-79) exists in Amazon OpenSearch Dashboards.
Check the vendor advisory for the affected versions of Amazon OpenSearch Dashboards.
Severity: High (CVSS 8.7/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Amazon OpenSearch Dashboards を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- AWS aws.amazon.com
- web aws.amazon.com
- web github.com
- web github.com
- web nvd.nist.gov
- web aws.amazon.com
- web github.com