#13412·cesium

wasm-unsafe-eval error after upgrading to 1.139.0

Author: CesiumBenCreated Apr 16, 2026Updated Sep 17, 2026
Labelstype - bugneeds triage

What happened?

Some users are getting this error after upgrading to later versions of CesiumJS. The version delta is at least from 1.122.0 to 1.139.0. Prior to that this error did not occur, so some later implementation is conflicting with their CSP. If there isn't a list of required security headers, it would be helpful to have one.

Uncaught EvalError: Evaluating a string Cesium.js:16504 as JavaScript violates the following Content Security Policy directive because 'unsafe-eval' is not an allowed source of script: default-src 'self' (URLs listed) blob: 'wasm-unsafe-eval'

Related community issues on CSP with CeisumJS: https://community.cesium.com/t/using-cesium-with-csp-settings/12663/2 https://community.cesium.com/t/csp-security-header-issues-with-cesium-in-react-application/35550 https://community.cesium.com/t/using-cesium-with-csp-settings/12663

Reproduction steps

Occurs with application load with later versions of CesiumJS

Sandcastle example

No response

Environment

Browser: Any CesiumJS Version: 1.139.0 (Migration from 1.122.0) Operating System: Mac

AI acknowledgment

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