CVE-2026-84942
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.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, but only after tricking someone into an action such as opening a file or a link.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Fastnexa security experts
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Scoring
- CVSS
- 8.7 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N- CVSS v4
- 6.3
- Weakness
- CWE-79
- Assigned by
- ff89ba41-3aa1-4d27-914a-91399e9639e5
Dates
- Published
- 2026-09-08
- Last modified
- 2026-09-09
- Sources
- NVD