{"id":"CVE-2026-18420","state":"PUBLISHED","title":"RCE via Prototype Pollution in OpenSearch Dashboards","description":"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.","publishedAt":"2026-08-20T20:40:40.709Z","updatedAt":"2026-08-25T19:19:07.471Z","severity":{"score":8.7,"label":"High","version":"4.0","vector":"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","source":"AMZN"},"assigner":"AMZN","products":["AWS Amazon OpenSearch Service","OpenSearch OpenSearch Dashboards"],"affected":[{"vendor":"AWS","product":"Amazon OpenSearch Service","defaultStatus":"unaffected","versions":[{"version":"3.0.0","status":"affected","lessThan":"3.8.0","versionType":"custom"}]},{"vendor":"OpenSearch","product":"OpenSearch Dashboards","defaultStatus":"unaffected","versions":[{"version":"3.0.0","status":"affected","lessThan":"3.8.0","versionType":"custom"}]}],"references":["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","https://aws.amazon.com/security/security-bulletins/2026-085-aws/"],"weaknesses":["CWE-1321"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/18xxx/CVE-2026-18420.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-18420","state":"PUBLISHED","datePublished":"2026-08-20T20:40:40.709Z","dateUpdated":"2026-08-25T19:19:07.471Z","assignerShortName":"AMZN","assignerOrgId":"ff89ba41-3aa1-4d27-914a-91399e9639e5","dateReserved":"2026-07-30T18:11:08.464Z"},"containers":{"cna":{"title":"RCE via Prototype Pollution in OpenSearch Dashboards","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"AWS","product":"Amazon OpenSearch Service","defaultStatus":"unaffected","versions":[{"version":"3.0.0","status":"affected","lessThan":"3.8.0","versionType":"custom"}]},{"vendor":"OpenSearch","product":"OpenSearch Dashboards","defaultStatus":"unaffected","versions":[{"version":"3.0.0","status":"affected","lessThan":"3.8.0","versionType":"custom"}]}],"references":[{"url":"https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/3.8.0","tags":["patch"]},{"url":"https://github.com/opensearch-project/OpenSearch-Dashboards/security/advisories/GHSA-xmqx-xq2p-8jq2","tags":["third-party-advisory"]},{"url":"https://aws.amazon.com/security/security-bulletins/2026-085-aws/","tags":["vendor-advisory"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseSeverity":"HIGH","baseScore":8.8,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}},{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","subConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"HIGH","baseScore":8.7,"vectorString":"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"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1321","lang":"en","description":"CWE-1321 Improperly controlled modification of object prototype attributes ('prototype pollution')","type":"CWE"}]}],"providerMetadata":{"shortName":"AMZN","orgId":"ff89ba41-3aa1-4d27-914a-91399e9639e5","dateUpdated":"2026-08-20T20:40:40.709Z"},"impacts":[{"capecId":"CAPEC-586","descriptions":[{"lang":"en","value":"CAPEC-586 Object Injection"}]}],"cpeApplicability":[{"operator":"OR","nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:aws:amazon_opensearch_service:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0.0","versionEndExcluding":"3.8.0"}]},{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:opensearch:opensearch_dashboards:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0.0","versionEndExcluding":"3.8.0"}]}]}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 1.0.4"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-25T19:18:58.456470Z","id":"CVE-2026-18420","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-25T19:19:07.471Z"}}]}}}