FAQ-001142 - Lightning Web Components and JavaScript Security / Third-Party Libraries and External APIs

Yes, there are security restrictions on using third-party JavaScript libraries that manipulate the DOM in Lightning Web Components (LWCs): **Key Restrictions:** - **Static Resources**: All JavaScript files must be stored in static resources and loaded from there, rather than being dynamically loaded from third-party endpoints or CDNs. This ensures version control and security reviews. - **Lightning Locker Compliance**: The libraries must comply with Lightning Locker, which enforces strict security policies, including DOM isolation and restricted access to global objects. - **Avoid Unsafe Practices**: You must avoid using unsafe attributes or methods that could lead to vulnerabilities like cross-site scripting (XSS). Ensure the library doesn't use unsafe methods or attributes. - **Sanitization Responsibility**: The framework doesn't automatically encode HTML, so you must sanitize or encode user-controlled data before rendering it in the DOM. - **Secure Libraries**: Any third-party libraries used should be secure and included as static resources to comply with Salesforce's security policies. - **Security Reviews**: The libraries should undergo security reviews to ensure they don't introduce vulnerabilities. By following these restrictions, you can maintain the security and integrity of your application while using third-party JavaScript libraries that manipulate the DOM.

The FAQ content was updated to improve clarity and tone consistency following the brand guidelines. Changes made: 1) Replaced 'Developers must avoid' with 'You must avoid' for more direct, conversational tone. 2) Changed 'LockerService' to 'Lightning Locker' for current terminology accuracy. 3) Converted 'ensure the library does not use' to 'ensure the library doesn't use' for conversational contractions. 4) Changed 'The framework does not automatically encode' to 'The framework doesn't automatically encode' for consistency. 5) Replaced 'By adhering to these restrictions' with 'By following these restrictions' for simpler language. The security rules selected relate directly to the FAQ's JavaScript security content: AvoidCreateElementScriptLinkTag prevents dynamic creation of script elements which relates to the FAQ's point about loading from static resources instead of dynamically. LoadJavaScriptHtmlScript and LoadJavaScriptIncludeScript detect improper JavaScript loading methods which connects to the static resources requirement. @lwc/lwc/no-inner-html prevents unsafe DOM manipulation through innerHTML which relates to the FAQ's discussion of avoiding unsafe DOM practices and XSS prevention. The LibraryWithKnown*SeverityVulnerability rules detect vulnerable third-party libraries which directly relates to the FAQ's emphasis on using secure libraries and security reviews. AvoidUnescapedHtmlInAura relates to the FAQ's point about sanitization responsibility and preventing XSS through proper encoding.