Even though we can detect that the server buffer is too small to
receive the APDU result we don't prevent the actual copy of this result
to allocated buffer which results in overflow.
Before this change we announce that we support redirection
packet version 3 (Microsoft RDP 5.1 and 5.2 clients), this
makes the server to only send back LB_TARGET_NET_ADDRESS which
includes an IP address for the redirection. Announcing version
4 (Microsoft RDP 6.0 and 6.1 clients) will make the server to
send a LB_TARGET_FQDN which solves a few problems, for example
using kerberos authentication.
Fixes issue #303
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
There is a limiter used for processing X11 events set to 20
for slicing between processing X11 event and processing data
on file descriptors. Before this fix, when waiting for data on
filedescriptors, we assumed that there were no pending X11
events left on queue and therefore the select() timeout on
60 seconds.
Now we will check the queue and select a timeout depending
on whats left to do.
Fixes bug #275
Current approach for TS_SCardEstablishContext() causes
Windows not to detect scard reader insertion in a case
when rdesktop was lauched without attached reader(s).
Thanks to demansong@gmail.com for the help to pinpoint this issue.
Upon a redirection, we have received a cookie that is used
for authentication and we should not flag this as a pin
code for the smartcard. This solves a problem with incorrect
pin code when using smart card authentication and if
redirected to a server were a session exists.
We need to track the desired session size even if we can resize
without a reconnect. Otherwise we will request the wrong size in
the event we need to reconnect for another reason (e.g. network
problems).
If tcp_connect is called with the same server name, don't look up the
address again. This avoids connecting to other servers when using a
round-robin RDS farm name, as recommended by Microsoft.
This introduces a backwards-incompatible change. If rdesktop was
reconnecting because the user was moving between networks and the
server is no longer reachable on the same address, the user must
re-start rdesktop to reach their server.
We have seen different behaviour between versions of Windows RDP
servers how a connection should be closed and rdesktop should exit.
Windows 2008 server and earlier versions sets an error info value of
0 and then sends deactivate PDU. Later versions sends a error info
of vlaue 12 (User initiated logoff) but does not send deactivate PDU.
A work around was added to translate this case for Windows 2008 and
earlier to newer aporach to get proper handling.
This prevents reconnect loop introduced when hitting ESC or wait for
timeout at logon screen against 2008 server or earlier.
This commit also fixes a problem where a reconnect loop was triggerd
even if no required 'auto-reconnect cookie' is received from the server.
