CVE-2018-20182 (published 2019-03-15T18:29Z)

rdesktop versions up to and including v1.8.3 contain a Buffer Overflow over the global variables in the function seamless_process_line() that results in memory corruption and probably even a remote code execution.

Severity: HIGH
CVSS v2 base score: 7.5 (AV:N/AC:L/Au:N/C:P/I:P/A:P)
CVSS v3 base score: 9.8, CRITICAL (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)

Weakness information:
cwe_id: CWE-119
cwe_name: Improper Restriction of Operations within the Bounds of a Memory Buffer
description: The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
extended_description: 
            Certain languages allow direct addressing of memory locations and do not automatically ensure that these locations are valid for the memory buffer that is being referenced. This can cause read or write operations to be performed on memory locations that may be associated with other variables, data structures, or internal program data.
         
         

Fix information:
repo_url: https://github.com/rdesktop/rdesktop
commit_details: repo_url: https://github.com/rdesktop/rdesktop
author: Henrik Andersson
author_date: 2019-01-16 10:45:33+01:00
msg: Malicious RDP server security fixes

This commit includes fixes for a set of 21 vulnerabilities in
rdesktop when a malicious RDP server is used.

All vulnerabilities was identified and reported by Eyal Itkin.

 * Add rdp_protocol_error function that is used in several fixes
 * Refactor of process_bitmap_updates
 * Fix possible integer overflow in s_check_rem() on 32bit arch
 * Fix memory corruption in process_bitmap_data - CVE-2018-8794
 * Fix remote code execution in process_bitmap_data - CVE-2018-8795
 * Fix remote code execution in process_plane - CVE-2018-8797
 * Fix Denial of Service in mcs_recv_connect_response - CVE-2018-20175
 * Fix Denial of Service in mcs_parse_domain_params - CVE-2018-20175
 * Fix Denial of Service in sec_parse_crypt_info - CVE-2018-20176
 * Fix Denial of Service in sec_recv - CVE-2018-20176
 * Fix minor information leak in rdpdr_process - CVE-2018-8791
 * Fix Denial of Service in cssp_read_tsrequest - CVE-2018-8792
 * Fix remote code execution in cssp_read_tsrequest - CVE-2018-8793
 * Fix Denial of Service in process_bitmap_data - CVE-2018-8796
 * Fix minor information leak in rdpsnd_process_ping - CVE-2018-8798
 * Fix Denial of Service in process_secondary_order - CVE-2018-8799
 * Fix remote code execution in in ui_clip_handle_data - CVE-2018-8800
 * Fix major information leak in ui_clip_handle_data - CVE-2018-20174
 * Fix memory corruption in rdp_in_unistr - CVE-2018-20177
 * Fix Denial of Service in process_demand_active - CVE-2018-20178
 * Fix remote code execution in lspci_process - CVE-2018-20179
 * Fix remote code execution in rdpsnddbg_process - CVE-2018-20180
 * Fix remote code execution in seamless_process - CVE-2018-20181
 * Fix remote code execution in seamless_process_line - CVE-2018-20182
repository: repo_url: https://github.com/rdesktop/rdesktop
repo_name: rdesktop/rdesktop
description: 🚨 rdesktop is in need of a new maintainter. Please see the home page for more details. 🚨
repo_language: C
owner: rdesktop
file_changes: filename: asn.c
change_type: ModificationType.MODIFY
diff: @@ -22,7 +22,7 @@
 
 /* Parse an ASN.1 BER header */
 RD_BOOL
-ber_parse_header(STREAM s, int tagval, int *length)
+ber_parse_header(STREAM s, int tagval, uint32 *length)
 {
 	int tag, len;
 

programming_language: C
filename: bitmap.c
change_type: ModificationType.MODIFY
diff: @@ -794,7 +794,7 @@ process_plane(uint8 * in, int width, int height, uint8 * out, int size)
 					replen = revcode;
 					collen = 0;
 				}
-				while (collen > 0)
+				while (indexw < width && collen > 0)
 				{
 					color = CVAL(in);
 					*out = color;
@@ -802,7 +802,7 @@ process_plane(uint8 * in, int width, int height, uint8 * out, int size)
 					indexw++;
 					collen--;
 				}
-				while (replen > 0)
+				while (indexw < width && replen > 0)
 				{
 					*out = color;
 					out += 4;
@@ -824,7 +824,7 @@ process_plane(uint8 * in, int width, int height, uint8 * out, int size)
 					replen = revcode;
 					collen = 0;
 				}
-				while (collen > 0)
+				while (indexw < width && collen > 0)
 				{
 					x = CVAL(in);
 					if (x & 1)
@@ -844,7 +844,7 @@ process_plane(uint8 * in, int width, int height, uint8 * out, int size)
 					indexw++;
 					collen--;
 				}
-				while (replen > 0)
+				while (indexw < width && replen > 0)
 				{
 					x = last_line[indexw * 4] + color;
 					*out = x;

programming_language: C
filename: cliprdr.c
change_type: ModificationType.MODIFY
diff: @@ -118,6 +118,7 @@ cliprdr_process(STREAM s)
 	uint16 type, status;
 	uint32 length, format;
 	uint8 *data;
+	struct stream packet = *s;
 
 	in_uint16_le(s, type);
 	in_uint16_le(s, status);
@@ -127,6 +128,11 @@ cliprdr_process(STREAM s)
 	logger(Clipboard, Debug, "cliprdr_process(), type=%d, status=%d, length=%d", type, status,
 	       length);
 
+	if (!s_check_rem(s, length))
+	{
+		rdp_protocol_error("cliprdr_process(), consume of packet from stream would overrun", &packet);
+	}
+
 	if (status == CLIPRDR_ERROR)
 	{
 		switch (type)

programming_language: C
filename: constants.h
change_type: ModificationType.MODIFY
diff: @@ -751,6 +751,9 @@ enum RDP_DESKTOP_ORIENTATION
 #define ENC_SALTED_CHECKSUM		0x0010
 #define NO_BITMAP_COMPRESSION_HDR	0x0400
 
+/* [MS-RDPBCGR], TS_BITMAP_DATA, flags */
+#define BITMAP_COMPRESSION              0x0001
+
 /* orderFlags, [MS-RDPBCGR] 2.2.7.1.3 */
 #define NEGOTIATEORDERSUPPORT	0x0002
 #define ZEROBOUNDSDELTASSUPPORT 0x0008

programming_language: C
filename: cssp.c
change_type: ModificationType.MODIFY
diff: @@ -595,6 +595,7 @@ cssp_read_tsrequest(STREAM token, STREAM pubkey)
 	STREAM s;
 	int length;
 	int tagval;
+	struct stream packet;
 
 	s = tcp_recv(NULL, 4);
 
@@ -622,6 +623,7 @@ cssp_read_tsrequest(STREAM token, STREAM pubkey)
 
 	// receive the remainings of message
 	s = tcp_recv(s, length);
+	packet = *s;
 
 	// parse the response and into nego token
 	if (!ber_in_header(s, &tagval, &length) ||
@@ -632,6 +634,12 @@ cssp_read_tsrequest(STREAM token, STREAM pubkey)
 	if (!ber_in_header(s, &tagval, &length) ||
 	    tagval != (BER_TAG_CTXT_SPECIFIC | BER_TAG_CONSTRUCTED | 0))
 		return False;
+
+	if (!s_check_rem(s, length))
+	{
+		 rdp_protocol_error("cssp_read_tsrequest(), consume of version from stream would overrun",
+				    &packet);
+	}
 	in_uint8s(s, length);
 
 	// negoToken [1]
@@ -653,7 +661,14 @@ cssp_read_tsrequest(STREAM token, STREAM pubkey)
 		if (!ber_in_header(s, &tagval, &length) || tagval != BER_TAG_OCTET_STRING)
 			return False;
 
-		token->end = token->p = token->data;
+		if (!s_check_rem(s, length))
+		{
+			rdp_protocol_error("cssp_read_tsrequest(), consume of token from stream would overrun",
+					   &packet);
+		}
+
+		s_realloc(token, length);
+		s_reset(token);
 		out_uint8p(token, s->p, length);
 		s_mark_end(token);
 	}

programming_language: C
filename: lspci.c
change_type: ModificationType.MODIFY
diff: @@ -1,7 +1,8 @@
 /*  -*- c-basic-offset: 8 -*-
    rdesktop: A Remote Desktop Protocol client.
    Support for the Matrox "lspci" channel
-   Copyright (C) 2005 Matrox Graphics Inc. 
+   Copyright (C) 2005 Matrox Graphics Inc.
+   Copyright 2018 Henrik Andersson <hean01@cendio.se> for Cendio AB
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -134,6 +135,12 @@ lspci_process(STREAM s)
 	unsigned int pkglen;
 	static char *rest = NULL;
 	char *buf;
+	struct stream packet = *s;
+
+	if (!s_check(s))
+	{
+		rdp_protocol_error("lspci_process(), stream is in unstable state", &packet);
+	}
 
 	pkglen = s->end - s->p;
 	/* str_handle_lines requires null terminated strings */

programming_language: C
filename: mcs.c
change_type: ModificationType.MODIFY
diff: @@ -45,9 +45,16 @@ mcs_out_domain_params(STREAM s, int max_channels, int max_users, int max_tokens,
 static RD_BOOL
 mcs_parse_domain_params(STREAM s)
 {
-	int length;
+	uint32 length;
+	struct stream packet = *s;
 
 	ber_parse_header(s, MCS_TAG_DOMAIN_PARAMS, &length);
+
+	if (!s_check_rem(s, length))
+	{
+		rdp_protocol_error("mcs_parse_domain_params(), consume domain params from stream would overrun", &packet);
+	}
+
 	in_uint8s(s, length);
 
 	return s_check(s);
@@ -89,8 +96,9 @@ mcs_recv_connect_response(STREAM mcs_data)
 {
 	UNUSED(mcs_data);
 	uint8 result;
-	int length;
+	uint32 length;
 	STREAM s;
+	struct stream packet;
 	RD_BOOL is_fastpath;
 	uint8 fastpath_hdr;
 
@@ -99,6 +107,8 @@ mcs_recv_connect_response(STREAM mcs_data)
 
 	if (s == NULL)
 		return False;
+	
+	packet = *s;
 
 	ber_parse_header(s, MCS_CONNECT_RESPONSE, &length);
 
@@ -112,6 +122,12 @@ mcs_recv_connect_response(STREAM mcs_data)
 
 	ber_parse_header(s, BER_TAG_INTEGER, &length);
 	in_uint8s(s, length);	/* connect id */
+
+	if (!s_check_rem(s, length))
+	{
+		rdp_protocol_error("mcs_recv_connect_response(), consume connect id from stream would overrun", &packet);
+	}
+
 	mcs_parse_domain_params(s);
 
 	ber_parse_header(s, BER_TAG_OCTET_STRING, &length);

programming_language: C
filename: orders.c
change_type: ModificationType.MODIFY
diff: @@ -1259,11 +1259,17 @@ process_secondary_order(STREAM s)
 	uint16 flags;
 	uint8 type;
 	uint8 *next_order;
+	struct stream packet = *s;
 
 	in_uint16_le(s, length);
 	in_uint16_le(s, flags);	/* used by bmpcache2 */
 	in_uint8(s, type);
 
+	if (!s_check_rem(s, length + 7))
+	{
+		rdp_protocol_error("process_secondary_order(), next order pointer would overrun stream", &packet);
+	}
+
 	next_order = s->p + (sint16) length + 7;
 
 	switch (type)

programming_language: C
filename: proto.h
change_type: ModificationType.MODIFY
diff: @@ -164,6 +164,7 @@ RD_BOOL rdp_connect(char *server, uint32 flags, char *domain, char *password, ch
 		    char *directory, RD_BOOL reconnect);
 void rdp_reset_state(void);
 void rdp_disconnect(void);
+void rdp_protocol_error(const char *message, STREAM s);
 /* rdpdr.c */
 int get_device_index(RD_NTHANDLE handle);
 void convert_to_unix_filename(char *filename);
@@ -224,7 +225,7 @@ void tcp_run_ui(RD_BOOL run);
 /* asn.c */
 RD_BOOL ber_in_header(STREAM s, int *tagval, int *length);
 void ber_out_header(STREAM s, int tagval, int length);
-RD_BOOL ber_parse_header(STREAM s, int tagval, int *length);
+RD_BOOL ber_parse_header(STREAM s, int tagval, uint32 *length);
 void ber_out_integer(STREAM s, int value);
 void ber_out_sequence(STREAM s, STREAM contents);
 

programming_language: C
filename: rdp.c
change_type: ModificationType.MODIFY
diff: @@ -285,6 +285,19 @@ rdp_in_unistr(STREAM s, int in_len, char **string, uint32 * str_size)
 	size_t ibl, obl;
 	char *pin, *pout;
 
+	struct stream packet = *s;
+
+	if ((in_len < 0) || ((uint32)in_len >= (RD_UINT32_MAX / 2)))
+	{
+		logger(Protocol, Error, "rdp_in_unistr(), length of unicode data is out of bounds.");
+		abort();
+	}
+
+	if (!s_check_rem(s, in_len))
+	{
+		rdp_protocol_error("rdp_in_unistr(), consume of unicode data from stream would overrun", &packet);
+	}
+
 	// if not already open
 	if (!icv_utf16_to_local)
 	{
@@ -1211,6 +1224,7 @@ process_demand_active(STREAM s)
 {
 	uint8 type;
 	uint16 len_src_descriptor, len_combined_caps;
+	struct stream packet = *s;
 
 	/* at this point we need to ensure that we have ui created */
 	rd_create_ui();
@@ -1218,6 +1232,11 @@ process_demand_active(STREAM s)
 	in_uint32_le(s, g_rdp_shareid);
 	in_uint16_le(s, len_src_descriptor);
 	in_uint16_le(s, len_combined_caps);
+
+	if (!s_check_rem(s, len_src_descriptor))
+	{
+		rdp_protocol_error("rdp_demand_active(), consume of source descriptor from stream would overrun", &packet);
+	}
 	in_uint8s(s, len_src_descriptor);
 
 	logger(Protocol, Debug, "process_demand_active(), shareid=0x%x", g_rdp_shareid);
@@ -1390,78 +1409,113 @@ process_pointer_pdu(STREAM s)
 	}
 }
 
-/* Process bitmap updates */
-void
-process_bitmap_updates(STREAM s)
+/* Process TS_BITMAP_DATA */
+static void
+process_bitmap_data(STREAM s)
 {
-	uint16 num_updates;
 	uint16 left, top, right, bottom, width, height;
-	uint16 cx, cy, bpp, Bpp, compress, bufsize, size;
+	uint16 cx, cy, bpp, Bpp, flags, bufsize, size;
 	uint8 *data, *bmpdata;
-	int i;
-
+	
 	logger(Protocol, Debug, "%s()", __func__);
 
-	in_uint16_le(s, num_updates);
+	struct stream packet = *s;
 
-	for (i = 0; i < num_updates; i++)
-	{
-		in_uint16_le(s, left);
-		in_uint16_le(s, top);
-		in_uint16_le(s, right);
-		in_uint16_le(s, bottom);
-		in_uint16_le(s, width);
-		in_uint16_le(s, height);
-		in_uint16_le(s, bpp);
-		Bpp = (bpp + 7) / 8;
-		in_uint16_le(s, compress);
-		in_uint16_le(s, bufsize);
-
-		cx = right - left + 1;
-		cy = bottom - top + 1;
-
-		logger(Graphics, Debug,
-		       "process_bitmap_updates(), [%d,%d,%d,%d], [%d,%d], bpp=%d, compression=%d",
-		       left, top, right, bottom, width, height, Bpp, compress);
-
-		if (!compress)
-		{
-			int y;
-			bmpdata = (uint8 *) xmalloc(width * height * Bpp);
-			for (y = 0; y < height; y++)
-			{
-				in_uint8a(s, &bmpdata[(height - y - 1) * (width * Bpp)],
-					  width * Bpp);
-			}
-			ui_paint_bitmap(left, top, cx, cy, width, height, bmpdata);
-			xfree(bmpdata);
-			continue;
-		}
+	in_uint16_le(s, left); /* destLeft */
+	in_uint16_le(s, top); /* destTop */
+	in_uint16_le(s, right); /* destRight */
+	in_uint16_le(s, bottom); /* destBottom */
+	in_uint16_le(s, width); /* width */
+	in_uint16_le(s, height); /* height */
+	in_uint16_le(s, bpp); /*bitsPerPixel */
+	Bpp = (bpp + 7) / 8;
+	in_uint16_le(s, flags); /* flags */
+	in_uint16_le(s, bufsize); /* bitmapLength */
 
+	cx = right - left + 1;
+	cy = bottom - top + 1;
 
-		if (compress & 0x400)
-		{
-			size = bufsize;
-		}
-		else
-		{
-			in_uint8s(s, 2);	/* pad */
-			in_uint16_le(s, size);
-			in_uint8s(s, 4);	/* line_size, final_size */
-		}
-		in_uint8p(s, data, size);
+	/* FIXME: There are a assumtion that we do not consider in
+		this code. The value of bpp is not passed to
+		ui_paint_bitmap() which relies on g_server_bpp for drawing
+		the bitmap data.
+
+		Does this means that we can sanity check bpp with g_server_bpp ?
+	*/
+
+	if (Bpp == 0 || width == 0 || height == 0)
+	{
+        logger(Protocol, Warning, "%s(), [%d,%d,%d,%d], [%d,%d], bpp=%d, flags=%x", __func__,
+				left, top, right, bottom, width, height, bpp, flags);
+		rdp_protocol_error("TS_BITMAP_DATA, unsafe size of bitmap data received from server", &packet);
+	}
+
+	if ((RD_UINT32_MAX / Bpp) <= (width * height))
+	{
+		logger(Protocol, Warning, "%s(), [%d,%d,%d,%d], [%d,%d], bpp=%d, flags=%x", __func__,
+				left, top, right, bottom, width, height, bpp, flags);
+		rdp_protocol_error("TS_BITMAP_DATA, unsafe size of bitmap data received from server", &packet);
+	}
+ 
+	if (flags == 0)
+	{
+		/* read uncompressed bitmap data */
+		int y;
 		bmpdata = (uint8 *) xmalloc(width * height * Bpp);
-		if (bitmap_decompress(bmpdata, width, height, data, size, Bpp))
+		for (y = 0; y < height; y++)
 		{
-			ui_paint_bitmap(left, top, cx, cy, width, height, bmpdata);
+			in_uint8a(s, &bmpdata[(height - y - 1) * (width * Bpp)], width * Bpp);
 		}
-		else
-		{
-			logger(Graphics, Warning,
-			       "process_bitmap_updates(), failed to decompress bitmap");
-		}
-
+		
+		ui_paint_bitmap(left, top, cx, cy, width, height, bmpdata);
 		xfree(bmpdata);
+		return;
+	}
+
+	if (flags & NO_BITMAP_COMPRESSION_HDR)
+	{
+		size = bufsize;
+	}
+	else
+	{
+		/* Read TS_CD_HEADER */
+		in_uint8s(s, 2);        /* skip cbCompFirstRowSize (must be 0x0000) */
+		in_uint16_le(s, size);  /* cbCompMainBodySize */
+		in_uint8s(s, 2);        /* skip cbScanWidth */
+		in_uint8s(s, 2);        /* skip cbUncompressedSize */
+	}
+
+	/* read compressed bitmap data */
+	if (!s_check_rem(s, size))
+	{
+		rdp_protocol_error("process_bitmap_data(), consume of bitmap data from stream would overrun", &packet);
+	}
+	in_uint8p(s, data, size);
+	bmpdata = (uint8 *) xmalloc(width * height * Bpp);
+	if (bitmap_decompress(bmpdata, width, height, data, size, Bpp))
+	{
+		ui_paint_bitmap(left, top, cx, cy, width, height, bmpdata);
+	}
+	else
+	{
+		logger(Protocol, Warning, "%s(), failed to decompress bitmap", __func__);
+	}
+
+	xfree(bmpdata);
+}
+
+/* Process TS_UPDATE_BITMAP_DATA */
+void
+process_bitmap_updates(STREAM s)
+{
+	int i;
+	uint16 num_updates;
+	
+	in_uint16_le(s, num_updates);   /* rectangles */
+
+	for (i = 0; i < num_updates; i++)
+	{
+		process_bitmap_data(s);
 	}
 }
 
@@ -2013,3 +2067,21 @@ rdp_disconnect(void)
 	logger(Protocol, Debug, "%s()", __func__);
 	sec_disconnect();
 }
+
+/* Abort rdesktop upon protocol error
+
+   A protocol error is defined as:
+
+    - A value is outside specified range for example;
+      bpp for a bitmap is not allowed to be greater than the
+      value 32 but is represented by a byte in protocol.
+
+*/
+void
+rdp_protocol_error(const char *message, STREAM s)
+{
+	logger(Protocol, Error, "%s(), %s", __func__, message);
+	if (s)
+		hexdump(s->p, s_length(s));
+	exit(0);
+}

programming_language: C
filename: rdpdr.c
change_type: ModificationType.MODIFY
diff: @@ -854,6 +854,7 @@ rdpdr_process(STREAM s)
 	uint16 vmin;
 	uint16 component;
 	uint16 pakid;
+	struct stream packet = *s;
 
 	logger(Protocol, Debug, "rdpdr_process()");
 	/* hexdump(s->p, s->end - s->p); */
@@ -873,8 +874,18 @@ rdpdr_process(STREAM s)
 				/* DR_CORE_SERVER_ANNOUNCE_REQ */
 				in_uint8s(s, 2);	/* skip versionMajor */
 				in_uint16_le(s, vmin);	/* VersionMinor */
+
 				in_uint32_le(s, g_client_id);	/* ClientID */
 
+				/* g_client_id is sent back to server,
+				   so lets check that we actually got
+				   valid data from stream to prevent
+				   that we leak back data to server */
+				if (!s_check(s))
+				{
+					rdp_protocol_error("rdpdr_process(), consume of g_client_id from stream did overrun", &packet);
+				}
+
 				/* The RDP client is responsibility to provide a random client id
 				   if server version is < 12 */
 				if (vmin < 0x000c)

programming_language: C
filename: rdpsnd.c
change_type: ModificationType.MODIFY
diff: @@ -269,6 +269,12 @@ rdpsnd_process_training(STREAM in)
 	uint16 tick;
 	uint16 packsize;
 	STREAM out;
+	struct stream packet = *in;
+
+	if (!s_check_rem(in, 4))
+	{
+		rdp_protocol_error("rdpsnd_process_training(), consume of training data from stream would overrun", &packet);
+	}
 
 	in_uint16_le(in, tick);
 	in_uint16_le(in, packsize);
@@ -445,6 +451,11 @@ rdpsnddbg_process(STREAM s)
 	static char *rest = NULL;
 	char *buf;
 
+	if (!s_check(s))
+	{
+		rdp_protocol_error("rdpsnddbg_process(), stream is in unstable state", s);
+	}
+
 	pkglen = s->end - s->p;
 	/* str_handle_lines requires null terminated strings */
 	buf = (char *) xmalloc(pkglen + 1);

programming_language: C
filename: seamless.c
change_type: ModificationType.MODIFY
diff: @@ -168,6 +168,12 @@ seamless_process_line(const char *line, void *data)
 
 			icon_buf[len] = strtol(byte, NULL, 16);
 			len++;
+
+			if ((size_t)len >= sizeof(icon_buf))
+			{
+				logger(Protocol, Warning, "seamless_process_line(), icon data would overrun icon_buf");
+				break;
+			}
 		}
 
 		ui_seamless_seticon(id, tok5, width, height, chunk, icon_buf, len);
@@ -370,6 +376,12 @@ seamless_process(STREAM s)
 {
 	unsigned int pkglen;
 	char *buf;
+	struct stream packet = *s;
+
+	if (!s_check(s))
+	{
+		rdp_protocol_error("seamless_process(), stream is in unstable state", &packet);
+	}
 
 	pkglen = s->end - s->p;
 	/* str_handle_lines requires null terminated strings */

programming_language: C
filename: secure.c
change_type: ModificationType.MODIFY
diff: @@ -296,6 +296,9 @@ sec_encrypt(uint8 * data, int length)
 void
 sec_decrypt(uint8 * data, int length)
 {
+	if (length <= 0)
+		return;
+
 	if (g_sec_decrypt_use_count == 4096)
 	{
 		sec_update(g_sec_decrypt_key, g_sec_decrypt_update_key);
@@ -848,9 +851,11 @@ sec_recv(RD_BOOL * is_fastpath)
 	uint16 sec_flags;
 	uint16 channel;
 	STREAM s;
+	struct stream packet;
 
 	while ((s = mcs_recv(&channel, is_fastpath, &fastpath_hdr)) != NULL)
 	{
+		packet = *s;
 		if (*is_fastpath == True)
 		{
 			/* If fastpath packet is encrypted, read data
@@ -859,6 +864,10 @@ sec_recv(RD_BOOL * is_fastpath)
 			fastpath_flags = (fastpath_hdr & 0xC0) >> 6;
 			if (fastpath_flags & FASTPATH_OUTPUT_ENCRYPTED)
 			{
+				if (!s_check_rem(s, 8)) {
+					rdp_protocol_error("sec_recv(), consume fastpath signature from stream would overrun", &packet);
+				}
+
 				in_uint8s(s, 8);	/* signature */
 				sec_decrypt(s->p, s->end - s->p);
 			}
@@ -875,6 +884,10 @@ sec_recv(RD_BOOL * is_fastpath)
 			{
 				if (sec_flags & SEC_ENCRYPT)
 				{
+					if (!s_check_rem(s, 8)) {
+						rdp_protocol_error("sec_recv(), consume encrypt signature from stream would overrun", &packet);
+					}
+
 					in_uint8s(s, 8);	/* signature */
 					sec_decrypt(s->p, s->end - s->p);
 				}
@@ -889,6 +902,10 @@ sec_recv(RD_BOOL * is_fastpath)
 				{
 					uint8 swapbyte;
 
+					if (!s_check_rem(s, 8)) {
+						rdp_protocol_error("sec_recv(), consume redirect signature from stream would overrun", &packet);
+					}
+
 					in_uint8s(s, 8);	/* signature */
 					sec_decrypt(s->p, s->end - s->p);
 

programming_language: C
filename: stream.h
change_type: ModificationType.MODIFY
diff: @@ -54,7 +54,7 @@ size_t in_ansi_string(STREAM s, char *string, size_t len);
 #define s_pop_layer(s,h)	(s)->p = (s)->h;
 #define s_mark_end(s)		(s)->end = (s)->p;
 #define s_check(s)		((s)->p <= (s)->end)
-#define s_check_rem(s,n)	((s)->p + n <= (s)->end)
+#define s_check_rem(s,n) (s_check(s) && (n <= (s)->end - (s)->p))
 #define s_check_end(s)		((s)->p == (s)->end)
 #define s_length(s)		((s)->end - (s)->data)
 #define s_left(s)               ((s)->size - ((s)->p - (s)->data))

programming_language: C
filename: types.h
change_type: ModificationType.MODIFY
diff: @@ -43,6 +43,8 @@ typedef signed short sint16;
 typedef unsigned int uint32;
 typedef signed int sint32;
 
+#define RD_UINT32_MAX (uint32)(-1)
+
 typedef void *RD_HBITMAP;
 typedef void *RD_HGLYPH;
 typedef void *RD_HCOLOURMAP;

programming_language: C++