{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-18420", "assignerOrgId": "ff89ba41-3aa1-4d27-914a-91399e9639e5", "state": "PUBLISHED", "assignerShortName": "AMZN", "dateReserved": "2026-07-30T18:11:08.464Z", "datePublished": "2026-08-20T20:40:40.709Z", "dateUpdated": "2026-08-20T20:40:40.709Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "ff89ba41-3aa1-4d27-914a-91399e9639e5", "shortName": "AMZN", "dateUpdated": "2026-08-20T20:40:40.709Z"}, "title": "RCE via Prototype Pollution in OpenSearch Dashboards", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-1321", "description": "CWE-1321 Improperly controlled modification of object prototype attributes ('prototype pollution')", "type": "CWE"}]}], "impacts": [{"capecId": "CAPEC-586", "descriptions": [{"lang": "en", "value": "CAPEC-586 Object Injection"}]}], "affected": [{"vendor": "AWS", "product": "Amazon OpenSearch Service", "versions": [{"status": "affected", "version": "3.0.0", "lessThan": "3.8.0", "versionType": "custom"}], "defaultStatus": "unaffected"}, {"vendor": "OpenSearch", "product": "OpenSearch Dashboards", "versions": [{"status": "affected", "version": "3.0.0", "lessThan": "3.8.0", "versionType": "custom"}], "defaultStatus": "unaffected"}], "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"}]}]}], "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.\u00a0\n\n\n\nTo remediate this issue, users should upgrade to OpenSearch Dashboards 3.8 or later.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p>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.&nbsp;</p><p>To remediate this issue, users should upgrade to OpenSearch Dashboards 3.8 or later.</p>"}]}], "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"}}], "source": {"discovery": "UNKNOWN"}, "x_generator": {"engine": "Vulnogram 1.0.4"}}}}

{}

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{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[3.0.0,3.8.0)"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "product": "amazon_opensearch_service", "vendor": "aws"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[3.0.0,3.8.0)"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "product": "opensearch_dashboards", "vendor": "opensearch"}], "created": "2026-08-21T00:30:07.428695+00:00", "updated": "2026-08-21T01:30:05.839739+00:00", "vendors": ["aws", "aws$PRODUCT$amazon_opensearch_service", "opensearch", "opensearch$PRODUCT$opensearch_dashboards"]}