CVE-2026-84942mediumCWE-79

CVE-2026-84942: medium-severity vulnerability in OpenSearch Dashboards

Stored Cross-Site Scripting via Vega Expression Function Bypass in OpenSearch Dashboards

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.3epss 0.5%
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 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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
Affected products
AWS · Amazon OpenSearch ServiceOpenSearch · OpenSearch Dashboards
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