{"id":"CVE-2026-18420","summary":"RCE via Prototype Pollution in OpenSearch Dashboards","details":"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. \n\n\n\nTo remediate this issue, users should upgrade to OpenSearch Dashboards 3.8 or later.","aliases":["GHSA-xmqx-xq2p-8jq2"],"modified":"2026-08-22T03:49:54.588734963Z","published":"2026-08-20T20:40:40.709Z","database_specific":{"cna_assigner":"AMZN","cwe_ids":["CWE-1321"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/18xxx/CVE-2026-18420.json"},"references":[{"type":"ADVISORY","url":"https://aws.amazon.com/security/security-bulletins/2026-085-aws/"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/18xxx/CVE-2026-18420.json"},{"type":"ADVISORY","url":"https://github.com/opensearch-project/OpenSearch-Dashboards/security/advisories/GHSA-xmqx-xq2p-8jq2"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-18420"},{"type":"FIX","url":"https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/3.8.0"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/opensearch-project/opensearch-dashboards","events":[{"introduced":"c378e1f95a58498ad41c4c99f39e2072b2629085"},{"fixed":"aa72a9818a045ad4e290a5eb9be59e025b90634d"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"3.0.0"},{"fixed":"3.8.0"}]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-18420.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"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"}]}