CVE-2026-3990

Medium

Description

A security flaw has been discovered in CesiumGS CesiumJS up to 1.137.0. Affected by this issue is some unknown functionality of the file Apps/Sandcastle/standalone.html. The manipulation of the argument c results in cross site scripting. The attack can be launched remotely. The exploit has been released to the public and may be used for attacks. The presence of this vulnerability remains uncertain at this time. The vendor was contacted early about this disclosure but did not respond in any way. According to CVE-2023-48094, "the vendor's position is that Apps/Sandcastle/standalone.html is part of the CesiumGS/cesium GitHub repository, but is demo code that is not part of the CesiumJS JavaScript library product."

SeverityMedium
CVSS4.3
Exploit probability—
ProductCesiumJS
PublishedMar 12, 2026
First seenMar 12, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
CesiumGS CesiumJS1.137—

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