CVE-2026-18420

Improper input validation in the Time Series Visual Builder (TSVB) plugin in OpenSearch Dashboards allows an authenticated remote user to execute arbitrary code on the server via a crafted JSON payload to the metrics visualization API endpoint. This issue is a form of prototype pollution that enables remote code execution. To remediate this issue, users should upgrade to OpenSearch Dashboards 3.8 or later.

Published Aug 20, 2026
CVSS 8.7 high
0.7% chance of exploitation in the next 30 days (EPSS)
A fix is available

Affected software

AWS Amazon OpenSearch Service
OpenSearch Dashboards

In the news

CVE-2026-18420 - Remote Code Execution via Prototype Pollution in OpenSearch Dashboards TSVB Plugin AWS Security Bulletins · Aug 20, 2026

CVE-2026-18420 at the National Vulnerability Database