Using the ruby methods for generating assembly blocks defined or
separated in prior commits, create a new payload from the existing
assembly blocks which performs a DNS lookup of the LHOST prior to
establishing a corresponding socket and downloading, and
decrypting the RC4 encrypted payload.
For anyone looking to learn how to build these payloads, these
three commits should provide a healthy primer. Small changes to
the payload structure can yield entropy enough to avoid signature
based detection by in-line or out-of-band static defenses. This
payload was completed in the time between this commit and the last.
Testing:
Win2k8r2
ToDo:
Update payload sizes when this branch is "complete"
Ensure UUIDs and adjacent black magic all work properly
Using the separation of block_recv and reverse_tcp, implement
reverse_tcp_dns using original shellcode as template with dynamic
injection of parameters. Concatenate the whole thing in the
generation call chain, and compile the resulting shellcode for
delivery.
Metasploit module pruned to bare minimum, with the LHOST OptString
moved into the library component.
Testing:
Win2k8r2
ToDo:
Update payload sizes when this branch is "complete"
Ensure UUIDs and adjacent black magic all work properly
Misc:
Clean up rc4.rb to use the rc4_keys method when generating a
stage. Makes the implementation far more readable and reduces
redundant code.
Convert reverse_tcp_rc4 and bind_tcp_rc4 from static shellcode
substitution payloads to metasm compiled assembly approach.
Splits up metasm methods for bind_tcp and reverse_tcp into socket
creation and block_recv to allow for reuse of the socket methods
with the RC4 payloads, while substituting the block_recv methods
for those carrying the appropriate decryptor stubs.
Creates a new rc4 module carrying the bulk of the decryptor and
adjacent convenince methods for standard payload generation.
Testing:
Tested against Win2k8r2, Win7x64, and WinXPx86
ToDo:
Ensure all the methods around payload sizing, UUIDs, and other
new functionality, the semantics of which i do not yet fully
understand, are appropriate and do not introduce breakage.
this method was absed around a char limit
for the desc column which no longer exists
trying to perform this operation generates an error
removing the method since it is not needed
RFC-7230 states that a Content-Length header is normally sent in
a POST request even when the value (length) is 0, indicating an
empty payload body. Rex HTTP client failed to follow this spec,
and caused some modules to fail (such as winrm_login).
Fix#6398
This patch fixes two problems:
1. 6820 - If the HTTP server returns a relative path
(example: /test), there is no host to extract, therefore the HOST
header in the HTTP request ends up being empty. When the web
server sees this, it might return an HTTP 400 Bad Request, and
the redirection fails.
2. 6806 - If the HTTP server returns a relative path that begins
with a dot, send_request_cgi! will literally send that in the
GET request. Since that isn't a valid GET request path format,
the redirection fails.
Fix#6806Fix#6820
I'm aware that this already exists as a post module, but there's nothing more annoying than having to bail out of Meterpreter, use the right module, set up the host list, etc all to just fire off a one-liner.
So this commit adds the command directly to Meterpreter's command line so that you don't have to do all that. This doesn't support specifying a file with the hosts in it (the post module does that). This is intended for quick resolution of particular hosts quickly.
This includes changes to the portfwd command so that the output is
nicer, things are easier to use, and users have the ability to create
reverse port forwards.
AR will start to complain about eager loading in command_dispatcher
/db.rb:519 because it references hosts as string without explicitly
stating that the table is being referenced.
Add a call .references in the AR call chain after the where clause
to silence this abysmal warning.
reimplement HD's work on a session interrupt handler
so that if an exploit fails the handler does not continue
waiting for a session that will never come
MS-385
Before, the datastore would store options case-sensitive, but would
access them case-insensitive, resulting is a number of string compares.
This commit stores options in their downcase form to reduce
update/lookup time. This adds up to reducing msfconsole boot time by
about 10% and rspec time by about 45 sec. (!) on my box.
One tricky part of this conversion is that there are several places (in
pro and framework) where we export or otherwise access the datastore as
a plain hash (case-sensitive). I believe I have caught all the ways we
access the datastore that are case-sensitive and substituted the
original key capitalization in those cases.
file:/ strings are special with some datastore options, causing them to read a
file rather than emitting the exact string. This causes a couple of problems.
1. the valid? check needs to be special on assignment, since normalization
really means normalizing the path, not playing with the value as we would do
for other types
2. there are races or simply out-of-order assignments when running commands
like 'services -p 80 -R', where the datastore option is assigned before the
file is actually written.
This is the 'easy' fix of disabling assignment validation (which we didn't have
before anyway) for types that can expect a file:/ prefix.
Options without a default were not pulled into the `@options` hash and
therefore were not used to validate options on assignment.
I am not entirely sure how this fix works, since it would seem that
non-override options would not get pulled in if an option was first set
in the global datastore. However, a previous value does not get
overridden and new values are validated. Anything further is merely
speculation on my part.
In current nomenclature, Rex Sockets are objects created by calls
to Rex::Socket::<Transport>.create and Rex::Socket.create_...
When the LocalHost or Comm parameters are set to remotely routed
addresses (currently via Meterpreter sessions), Rex will create a
Channel which will abstract communications with the remote end of
the session. These channel based abstractions are called pivots,
and present in three separate flavors:
1 - TcpClientChannel, a fully abstracted, selectable Socket.
2 - TcpServerChannel, a virtual Channel which distributes client
channels.
3 - UdpChannel, a virtual Channel which provides common methods for
UDP socket operations, but is not a full (selectable) abstraction.
Unfortunately this differentiation results in inconsistent returns
from the aforementioned socket creation calls, as the call chain
creates parameters and supplies them to the create method on the
comm object referenced in the params. The comm object may be a
channel, and produce a virtual representation of a socket with
functional methods analogous to Sockets, but without a kernel FD.
This commit begins the work of ensuring that all calls for socket
creation return selectable Rex::Socket objects with semantics
familiar to Ruby developers who have not read into the details of
Rex::Socket and Rex::Post.
-----
Summary of changes:
Convert Rex::IO::StreamAbstraction to SocketAbstraction and use
the new mixin in StreamAbstraction and DatagramAbstraction. This
approach allows for common methods to reuse the abstraction data
flow, while initializing separate types of socket obects and an
optional monitor as needed.
In the Rex::Post::Meterpreter namespace, extract common methods
from Stream to a SocketAbstraction mixin, include that mixin in
Stream, and add Datagram with the dio_write handler override
exported from the current implementation of UdpChannel, also using
the mixin. This relies on the Rex::IO work above to implement the
proper type of socket abstraction to the Channel descendants.
In Rex::Post::Meterpreter::Extensions::Stdapi::Net, convert the
UdpChannel to inherit from the Rex::Post::Meterpreter::Datagram
class, implementing only the send method at this tier. Convert
create_udp_channel to return the local socket side of the datagram
abstraction presented analogous to the TcpClientChannel approach
used before.
-----
Notes and intricacies:
In order to implement recvfrom on the UDP abstraction, a shim layer
has been put in place to forward the sockaddr information from the
remote peer to the local UDP socketpair in the abstraction. This
information takes up buffer space in the UDP socket, and in order
to maintain compatibility with consumers, the dio_write_handler
pushes the data buffer, and in a separate send call, he sockaddr
information from the remote socket. On the abstraction side, the
recvfrom_nonblock call of the real UDPSocket has been overriden
via the mixed in module to call the real method twice, once for
the data buffer, and once for the packed sockaddr data. The Rex
level consumer for recvfrom calls the underlying nonblock method
and expects this exact set of returns (as opposed to what standard
library UDPSocket.recvfrom returns, which is a data buffer and an
Array of sockaddr data).
-----
Testing:
Local and lab testing only so far.
Test RC script to be added in GH comments.
-----
Issues:
Currently, sendto on a remote socket does not appear to honor
LocalPort which causes DNS responses (#6611) to come from the
wrong port to remote clients being serviced over a pivot socket.
the preauth fingerprinting for postgres is somewhat
unmaintainable, but due to a specific customer request
i have added these two FPs for 9.4.1-5
MS-1102
Brent Cook
Louis Sato
darkbushido
RageLtMan
Adam Cammack
Metasploit
Jenkins
Jon Hart
wchen-r7
David Maloney
Christian Mehlmauer
dmohanty-r7
Rob Fuller
OJ
Brian Patterson
William Vu
join-us
thao doan
Rory McNamara
greg.mikeska@rapid7.com
Spencer McIntyre
James Lee
Justin Steven
greg.mikeska@rapid7.com
f7b053223a9e
Brendan Watters
Gregory Mikeska
Till Maas
HD Moore