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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-085-aws/
https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/3.8.0
https://github.com/opensearch-project/OpenSearch-Dashboards/security/advisories/GHSA-xmqx-xq2p-8jq2

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-20 21:17

Updated : 2026-08-25 20:16

NVD link : CVE-2026-18420

Mitre link : CVE-2026-18420

CVE.ORG link : CVE-2026-18420

JSON object : View

Products Affected

No product.

CWE

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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