What’s Vulnerable › Vulnerabilities

CVE-2026-3990: CesiumGS CesiumJS standalone.html cross site scripting

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-03-12 · updated 2026-06-17
• Weakness: CWE-79

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."

Affected products

• CesiumGS CesiumJS: 1.137

References

• https://github.com/AnalogyC0de/public_exp/issues/18
• https://vuldb.com/?ctiid.350473
• https://vuldb.com/?id.350473
• https://vuldb.com/?submit.769630

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