{"id":"CVE-2026-18420","aliases":["GHSA-xmqx-xq2p-8jq2"],"url":"https://o3.security/vulnerability/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.","published":"2026-08-20T20:40:40.709Z","modified":"2026-08-22T03:49:54.588734963Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":null,"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-22T03:49:54.588734963Z"}}