fix: path traversal in design serve /api/reload — arbitrary file read#752
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Gonzih wants to merge 1 commit intogarrytan:mainfrom
Open
fix: path traversal in design serve /api/reload — arbitrary file read#752Gonzih wants to merge 1 commit intogarrytan:mainfrom
Gonzih wants to merge 1 commit intogarrytan:mainfrom
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POST /api/reload accepts a { html: "/path/to/file.html" } body and
reads that file with fs.readFileSync() without path validation.
Any path the caller controls gets read and served via GET /.
Attack: POST /api/reload {"html": "/etc/passwd"}
→ GET / returns the contents of /etc/passwd
Fix: validate that the reload path resolves within the same directory
as the original HTML file passed to serve(). Paths outside that
directory are rejected with 403. Uses path.resolve() to canonicalize
before comparison.
Closes garrytan#672
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The Bug
`POST /api/reload` in `design/src/serve.ts` accepts a JSON body with an arbitrary `html` path and reads it with no validation:
```typescript
const newHtmlPath = body.html;
if (!newHtmlPath || !fs.existsSync(newHtmlPath)) { ... } // existence check only
htmlContent = fs.readFileSync(newHtmlPath, "utf-8"); // reads anything
```
The design server binds to localhost, but the Chrome extension (or any local process) can POST to it. Attack:
```
POST /api/reload {"html": "/etc/passwd"}
GET / → returns contents of /etc/passwd
```
Issue #672.
Fix
Validate that the reload path resolves within the same directory as the original HTML file. Paths outside are rejected with 403. The agent only ever reloads variant files in the same output directory — legitimate use is unaffected.
sent from mStack