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🛡️ Sentinel: [HIGH] Fix JavaScript Injection in ShiftScreen WebView #43

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🛡️ Sentinel: [HIGH] Fix JavaScript Injection in ShiftScreen WebView #43

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4 changes: 4 additions & 0 deletions .jules/sentinel.md
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Original file line number Diff line number Diff line change
@@ -0,0 +1,4 @@
## 2025-05-18 - [Insecure JavaScript Injection via String Interpolation in WebViews]
**Vulnerability:** Found a pattern in `src/screens/ShiftScreen.tsx` where string interpolation (`'${base64Json}'`) and manual quote replacement (`.replace(/'/g, "\\'")`) were used to pass a JSON payload directly into a `WebView`'s `injectJavaScript` function.
**Learning:** This approach creates an XSS / JS Injection vulnerability if the payload contains unescaped quotes or malicious executable sequences.
**Prevention:** To prevent this, always rely on `JSON.stringify()` to safely escape values before interpolating them into JavaScript code (e.g., `window.runTesseract(${JSON.stringify(base64Json)});`) rather than using manual text replacement and raw string interpolation.
51 changes: 24 additions & 27 deletions package-lock.json
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4 changes: 2 additions & 2 deletions src/screens/ShiftScreen.tsx
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Original file line number Diff line number Diff line change
Expand Up @@ -31,11 +31,11 @@ export default function ShiftScreen() {
setOcrText('');

const base64List = result.assets.map(a => `data:image/jpeg;base64,${a.base64}`);
const base64Json = JSON.stringify(base64List).replace(/'/g, "\\'");
const base64Json = JSON.stringify(base64List);

const jsCode = `
if (window.runTesseract) {
window.runTesseract('${base64Json}');
window.runTesseract(${JSON.stringify(base64Json)});
} else {
window.ReactNativeWebView.postMessage(JSON.stringify({ success: false, error: "Motore OCR non pronto." }));
}
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