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LWCExpertsecuritylockerthird-party

Review use of eval and dynamic script injection in third-party LWC wrapper

Real World Scenario

Vendor wrapper LWC loads analytics script via dynamic script tag and parses JSON config with Function constructor; security review flags before AppExchange submission.

Expected Answer

• Reject Function constructor and eval — blocked or restricted in Locker and LWS • Load third-party scripts only from approved static resources or documented CSP allowlist • Use JSON.parse not eval for config payloads • Vendor must provide Locker-compatible integration or LWS migration path • Security review checklist for AppExchange: no innerHTML with user data, no eval • Pen test dynamic script loading in Experience Cloud context • Document data sent to third parties in privacy assessment

Follow-Up Questions & Answers

Click to expand — each follow-up includes a direct, interview-ready answer

Direct answer: Reject Function constructor and eval — blocked or restricted in Locker and LWS Also consider: Load third-party scripts only from approved static resources or documented CSP allowlist In practice: Use JSON.parse not eval for config payloads Validate against production-scale constraints and long-term platform evolution.

Architect Perspective

AppExchange security rejects eval patterns — architect vendor selection with Locker compatibility upfront.