diff --git a/common/xrdp_constants.h b/common/xrdp_constants.h
index dc564fa0..163a3050 100644
--- a/common/xrdp_constants.h
+++ b/common/xrdp_constants.h
@@ -101,6 +101,13 @@
 #define CONNECTION_TYPE_LAN            0x06
 #define CONNECTION_TYPE_AUTODETECT     0x07
 
+/* Client Core Data: colorDepth, postBeta2ColorDepth (MS-RDPBCGR 2.2.1.3.2) */
+#define RNS_UD_COLOR_4BPP              0xCA00
+#define RNS_UD_COLOR_8BPP              0xCA01
+#define RNS_UD_COLOR_16BPP_555         0xCA02
+#define RNS_UD_COLOR_16BPP_565         0xCA03
+#define RNS_UD_COLOR_24BPP             0xCA04
+
 /* Slow-Path Input Event: messageType (MS-RDPBCGR 2.2.8.1.1.3.1.1) */
 /* TODO: to be renamed */
 #define RDP_INPUT_SYNCHRONIZE          0
diff --git a/libxrdp/xrdp_sec.c b/libxrdp/xrdp_sec.c
index fe7a460a..4de6c9ed 100644
--- a/libxrdp/xrdp_sec.c
+++ b/libxrdp/xrdp_sec.c
@@ -1608,10 +1608,10 @@ xrdp_sec_process_mcs_data_CS_CORE(struct xrdp_sec* self, struct stream* s)
     g_writeln("colorDepth 0x%4.4x (0xca00 4bpp 0xca01 8bpp)", colorDepth);
     switch (colorDepth)
     {
-        case 0xca00: /* RNS_UD_COLOR_4BPP */
+        case RNS_UD_COLOR_4BPP:
             self->rdp_layer->client_info.bpp = 4;
             break;
-        case 0xca01: /* RNS_UD_COLOR_8BPP */
+        case RNS_UD_COLOR_8BPP:
             self->rdp_layer->client_info.bpp = 8;
             break;
     }
@@ -1630,19 +1630,19 @@ xrdp_sec_process_mcs_data_CS_CORE(struct xrdp_sec* self, struct stream* s)
 
     switch (postBeta2ColorDepth)
     {
-        case 0xca00: /* RNS_UD_COLOR_4BPP */
+        case RNS_UD_COLOR_4BPP:
             self->rdp_layer->client_info.bpp = 4;
             break;
-        case 0xca01: /* RNS_UD_COLOR_8BPP */
+        case RNS_UD_COLOR_8BPP :
             self->rdp_layer->client_info.bpp = 8;
             break;
-        case 0xca02: /* RNS_UD_COLOR_16BPP_555 */
+        case RNS_UD_COLOR_16BPP_555:
             self->rdp_layer->client_info.bpp = 15;
             break;
-        case 0xca03: /* RNS_UD_COLOR_16BPP_565 */
+        case RNS_UD_COLOR_16BPP_565:
             self->rdp_layer->client_info.bpp = 16;
             break;
-        case 0xca04: /* RNS_UD_COLOR_24BPP */
+        case RNS_UD_COLOR_24BPP:
             self->rdp_layer->client_info.bpp = 24;
             break;
     }