diff --git a/client/src/uart/uart_posix.c b/client/src/uart/uart_posix.c
index cf0837845..8a624934d 100644
--- a/client/src/uart/uart_posix.c
+++ b/client/src/uart/uart_posix.c
@@ -93,12 +93,27 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
     // init timeouts
     timeout.tv_usec = UART_FPC_CLIENT_RX_TIMEOUT_MS * 1000;
 
-    if (memcmp(pcPortName, "tcp:", 4) == 0) {
-        struct addrinfo *addr = NULL, *rp;
-        char *addrstr = strdup(pcPortName + 4);
+    char *prefix = strdup(pcPortName);
+    if (prefix == NULL) {
+        PrintAndLogEx(ERR, "error: malloc");
+        free(sp);
+        return INVALID_SERIAL_PORT;
+    }
+    str_lower(prefix);
 
+    if (memcmp(prefix, "tcp:", 4) == 0) {
+        free(prefix);
+
+        if (strlen(pcPortName) <= 4) {
+            free(sp);
+            return INVALID_SERIAL_PORT;
+        }
+
+        struct addrinfo *addr = NULL, *rp;
+
+        char *addrstr = strdup(pcPortName + 4);
         if (addrstr == NULL) {
-            printf("Error: strdup\n");
+            PrintAndLogEx(ERR, "error: malloc");
             free(sp);
             return INVALID_SERIAL_PORT;
         }
@@ -122,7 +137,7 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
 
         int s = getaddrinfo(addrstr, portstr, &info, &addr);
         if (s != 0) {
-            printf("Error: getaddrinfo: %s\n", gai_strerror(s));
+            PrintAndLogEx(ERR, "error: getaddrinfo: %s", gai_strerror(s));
             freeaddrinfo(addr);
             free(addrstr);
             free(sp);
@@ -143,7 +158,7 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
         }
 
         if (rp == NULL) {               /* No address succeeded */
-            printf("Error: Could not connect\n");
+            PrintAndLogEx(ERR, "error: Could not connect");
             freeaddrinfo(addr);
             free(addrstr);
             free(sp);
@@ -164,16 +179,18 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
         return sp;
     }
 
-    if (memcmp(pcPortName, "bt:", 3) == 0) {
+    if (memcmp(prefix, "bt:", 3) == 0) {
+         free(prefix);
+
 #ifdef HAVE_BLUEZ
         if (strlen(pcPortName) != 20) {
             free(sp);
             return INVALID_SERIAL_PORT;
         }
-        char *addrstr = strndup(pcPortName + 3, 17);
 
+        char *addrstr = strndup(pcPortName + 3, 17);
         if (addrstr == NULL) {
-            printf("Error: malloc\n");
+            PrintAndLogEx(ERR, "error: malloc");
             free(sp);
             return INVALID_SERIAL_PORT;
         }
@@ -214,7 +231,9 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
     // Is local socket buffer, not a TCP or any net connection!
     // so, you can't connect with address like: 127.0.0.1, or any IP
     // see http://man7.org/linux/man-pages/man7/unix.7.html
-    if (memcmp(pcPortName, "socket:", 7) == 0) {
+    if (memcmp(prefix, "socket:", 7) == 0) {
+        free(prefix);
+
         if (strlen(pcPortName) <= 7) {
             free(sp);
             return INVALID_SERIAL_PORT;
@@ -255,6 +274,8 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
         return sp;
     }
 
+    free(prefix);
+
     sp->fd = open(pcPortName, O_RDWR | O_NOCTTY | O_NDELAY | O_NONBLOCK);
     if (sp->fd == -1) {
         uart_close(sp);
@@ -311,7 +332,7 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
         speed = 115200;
         if (!uart_set_speed(sp, speed)) {
             uart_close(sp);
-            printf("[!] UART error while setting baudrate\n");
+            PrintAndLogEx(ERR, "UART error while setting baudrate");
             return INVALID_SERIAL_PORT;
         }
     }