CVE-2026-18420highCWE-1321

CVE-2026-18420: high-severity vulnerability in OpenSearch Dashboards

RCE via Prototype Pollution in OpenSearch Dashboards

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.7epss 1.0%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
AWS · Amazon OpenSearch ServiceOpenSearch · OpenSearch Dashboards
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