### Summary goshs contains a cross-site request forgery issue in its state-changing HTTP GET routes. An external attacker can cause an already authenticated browser to trigger destructive actions such as `?delete` and `?mkdir` because goshs relies on HTTP basic auth alone and performs no CSRF, `Origin`, or `Referer` validation for those routes. I reproduced this on `v2.0.0-beta.5`. ### Details The vulnerable request handling is reachable through normal GET requests: - `httpserver/handler.go:118-123` dispatches `?mkdir` directly to `handleMkdir()` - `httpserver/handler.go:180-186` dispatches `?delete` directly to `deleteFile()` Authentication is enforced only by HTTP basic auth: - `httpserver/middleware.go:20-87` accepts any request that presents valid cached or replayed basic-auth credentials The resulting state changes hit filesystem mutation sinks: - `httpserver/handler.go:683-718` calls `os.RemoveAll()` in `deleteFile()` - `httpserver/handler.go:961-1000` calls `os.MkdirAll()` in `handleMkdir()` Because browsers can replay HTTP basic-auth credentials on subresource requests, an attacker-controlled page can embed: - `

` - `

` If the victim has already authenticated to goshs, those requests are treated as legitimate authenticated actions and the server mutates the filesystem. ### PoC Manual verification commands used: `Terminal 1` ```bash cd '/Users/r1zzg0d/Documents/CVE hunting/targets/goshs_beta5' go build -o /tmp/goshs_beta5 ./ rm -rf /tmp/goshs_csrf_root /tmp/goshs_csrf_site mkdir -p /tmp/goshs_csrf_root /tmp/goshs_csrf_site printf 'delete me\n' > /tmp/goshs_csrf_root/victim.txt cat > /tmp/goshs_csrf_site/delete.html <<'HTML'

HTML cat > /tmp/goshs_csrf_site/mkdir.html <<'HTML'