diff --git a/engine/client/parse/cl_parse.c b/engine/client/parse/cl_parse.c
index e91b93f5..373789c7 100644
--- a/engine/client/parse/cl_parse.c
+++ b/engine/client/parse/cl_parse.c
@@ -891,6 +891,15 @@ static void CL_ParseServerData( sizebuf_t *msg, connprotocol_t proto )
 		}
 	}
 
+	if( cl.playernum < 0 || cl.playernum >= MAX_CLIENTS || cl.maxclients < 0 || cl.maxclients >= MAX_CLIENTS )
+	{
+		Con_Printf( S_ERROR "%s: invalid playernum or maxclients (%d and %d must be less than %d)\n", __func__,
+			cl.playernum, cl.maxclients, MAX_CLIENTS );
+		CL_Disconnect_f();
+		Host_AbortCurrentFrame();
+		return;
+	}
+
 	Q_snprintf( mapfile, sizeof( mapfile ), "maps/%s.bsp", clgame.mapname );
 	if( CRC32_MapFile( &cl.worldmapCRC, mapfile, cl.maxclients > 1 ))
 	{
diff --git a/engine/client/parse/cl_qparse.c b/engine/client/parse/cl_qparse.c
index 90a9d3af..4d0ad624 100644
--- a/engine/client/parse/cl_qparse.c
+++ b/engine/client/parse/cl_qparse.c
@@ -973,12 +973,21 @@ void CL_ParseQuakeMessage( sizebuf_t *msg )
 			break;
 		case svc_updatename:
 			param1 = MSG_ReadByte( msg );
+			if( param1 >= ARRAYSIZE( cl.players ))
+			{
+				MSG_ReadString( msg );
+				break;
+			}
+
 			Q_strncpy( cl.players[param1].name, MSG_ReadString( msg ), sizeof( cl.players[0].name ));
 			Q_strncpy( cl.players[param1].model, "player", sizeof( cl.players[0].name ));
 			break;
 		case svc_updatefrags:
 			param1 = MSG_ReadByte( msg );
 			param2 = MSG_ReadShort( msg );
+			if( param1 >= ARRAYSIZE( cl.players ))
+				break;
+
 			// HACKHACK: store frags into spectator
 			cl.players[param1].spectator = param2;
 			break;
@@ -994,6 +1003,9 @@ void CL_ParseQuakeMessage( sizebuf_t *msg )
 		case svc_updatecolors:
 			param1 = MSG_ReadByte( msg );
 			param2 = MSG_ReadByte( msg );
+			if( param1 >= ARRAYSIZE( cl.players ) || param2 >= ARRAYSIZE( cl.players ))
+				break;
+
 			cl.players[param1].topcolor = param2 & 0xF;
 			cl.players[param1].bottomcolor = (param2 & 0xF0) >> 4;
 			break;