diff --git a/httplib.h b/httplib.h
index 092940e..1836b20 100644
--- a/httplib.h
+++ b/httplib.h
@@ -4204,7 +4204,7 @@ inline void Server::stop() {
 inline bool Server::parse_request_line(const char *s, Request &req) {
   const static std::regex re(
       "(GET|HEAD|POST|PUT|DELETE|CONNECT|OPTIONS|TRACE|PATCH|PRI) "
-      "(([^?]+)(?:\\?(.*?))?) (HTTP/1\\.[01])\r\n");
+      "(([^? ]+)(?:\\?([^ ]*?))?) (HTTP/1\\.[01])\r\n");
 
   std::cmatch m;
   if (std::regex_match(s, m, re)) {
diff --git a/test/test.cc b/test/test.cc
index 9eb577b..8222125 100644
--- a/test/test.cc
+++ b/test/test.cc
@@ -3004,6 +3004,12 @@ TEST(ServerRequestParsingTest, InvalidHeaderTextWithExtraCR) {
                    "Content-Type: text/plain\r\n\r");
 }
 
+TEST(ServerRequestParsingTest, InvalidSpaceInURL) {
+  std::string out;
+  test_raw_request("GET /h i HTTP/1.1\r\n\r\n", &out);
+  EXPECT_EQ("HTTP/1.1 400 Bad Request", out.substr(0, 24));
+}
+
 TEST(ServerStopTest, StopServerWithChunkedTransmission) {
   Server svr;