Fix: path traversal in HttpServer default callback - #608
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The default HttpServer callback built the filesystem path as "." + uri without sanitizing .. segments, allowing a remote unauthenticated client to read files outside the document root with a request like GET /../secret.txt. Add sanitizeUri() which resolves . and .. lexically, clamping any attempt to escape above the virtual root so the path stays within the document root directory. Reported by Yeongtaek Yoo (GitHub: @yt010108). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
HttpServercallback built the filesystem path as"." + uriwithout sanitizing..segments, letting a remote unauthenticated client read files outside the document root (e.g.GET /../secret.txt).sanitizeUri()which resolves.and..lexically, clamping any escape above the virtual root so the resulting path always stays within the document root.response_head_filethat were over the 100-column limit.Affected entry points
IXHttpServerdefault connection callback (used by thehttpdexample andws httpdcommand when no custom callback is installed).Credit
Reported by Yeongtaek Yoo (GitHub: @yt010108).
Test plan
ws httpdfrom a directory that has a sibling directory with a secret file.curl http://localhost:<port>/../secret.txt— should return 404, not the file contents.curl http://localhost:<port>/index.html— should still serve normally.🤖 Generated with Claude Code