CVE-2026-53624

### Summary The `helmet` middleware in gofiber/fiber never sets the `Strict-Transport-Security` (HSTS) response header, even when `HSTSMaxAge` is explicitly configured, because the condition check at `helmet.go:67` uses `c.Protocol()` — which returns the HTTP protocol version string (e.g., `"HTTP/1.1"`, `"HTTP/2.0"`) — instead of `c.Scheme()` — which returns the URL scheme (`"http"` or `"https"`). Since `c.Protocol()` never equals `"https"` in any real deployment, the HSTS header is permanently disabled, defeating the security protection. ### Details **Root cause:** `middleware/helmet/helmet.go`, line 67: ```go if c.Protocol() == "https" && cfg.HSTSMaxAge != 0 { ``` `c.Protocol()` (defined at `req.go:865-867`) delegates to `fasthttp.Request.Header.Protocol()`, which returns the HTTP protocol version: - `"HTTP/1.1"` for HTTP/1.1 connections - `"HTTP/2.0"` for HTTP/2 connections The correct method is `c.Scheme()` (defined at `req.go:844-862`), which returns: - `"http"` for plain HTTP connections - `"https"` for TLS connections Since `"HTTP/1.1" != "https"` always evaluates to `true`, the entire HSTS block (lines 67-76) is dead code. **Note on test coverage:** The existing helmet test (`helmet_test.go`) passes because it uses `ctx.Request.Header.SetProtocol("https")` to artificially force `Protocol()` to return `"https"`. However, `fasthttp.Request.Header.SetProtocol()` sets the HTTP version field, and real HTTP requests never have protocol `"https"` — they have `"HTTP/1.1"` or `"HTTP/2.0"`. The test is validating the wrong thing. ### PoC **Clean-checkout maintainer-runnable recipe:** 1. Save the following as `middleware/helmet/poc_hsts_test.go`: ```go package helmet import ( "crypto/tls" "net/http/httptest" "testing" "github.com/gofiber/fiber/v3" ) func Test_PoC_HSTS_NeverSet(t *testing.T) { app := fiber.New() app.Use(New(Config{ HSTSMaxAge: 31536000, })) app.Get("/", func(c fiber.Ctx) error { return c.Sen