{"id":"CVE-2026-84942","title":"Improper input validation in the Vega expression function implementation in OpenSearch Dashboards allows a remote authenticated actor with dashboard write permissions to execute arbitrary JavaScript in the context of other users' browser…","summary":"Improper input validation in the Vega expression function implementation in OpenSearch Dashboards allows a remote authenticated actor with dashboard write permissions to execute arbitrary JavaScript in the context of other users' browser…","severity":"high","cvss":8.7,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N","cwe":["CWE-79"],"vendor":"AWS","product":"Amazon OpenSearch Service","affected":["amazon_opensearch_service","dashboards >= v2.0.0 <= v3.5.0"],"published":"2026-09-08","updated":"2026-09-09","sourceUpdated":"2026-09-09T21:17:05.473","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-84942","references":[{"url":"https://aws.amazon.com/security/security-bulletins/2026-102-aws/","label":"ff89ba41-3aa1-4d27-914a-91399e9639e5"},{"url":"https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/2.19.5","label":"ff89ba41-3aa1-4d27-914a-91399e9639e5"},{"url":"https://github.com/opensearch-project/OpenSearch-Dashboards/releases/tag/3.6.0","label":"ff89ba41-3aa1-4d27-914a-91399e9639e5"}],"tags":["nvd","cve.org"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-09-09T20:45:08.722192Z"},"epss":0.00544,"epssPercentile":0.43296,"ingestedAt":"2026-09-08T20:10:03.220Z","slug":"CVE-2026-84942","body":"## Overview\n\nImproper input validation in the Vega expression function implementation in OpenSearch Dashboards allows a remote authenticated actor with dashboard write permissions to execute arbitrary JavaScript in the context of other users' browser sessions by saving a crafted Vega visualization. The checkForFunctionProperty validation routine failed to recurse into arrays of objects, allowing a function property nested inside an array to bypass validation.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":47.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}