Due to the modular structure of payload stages its pretty trivial
to add DNS resolution instead of hard-coded IP address in stage0.
The only real complication here is that ReverseConnectRetries ends
up being one byte further down than in the original shellcode. It
appears that the original rev_tcp_dns payload suffers from the same
issue.
Hostname substitution is handled in the same method as the RC4 and
XOR keys, with an offset provided and replace_vars ignoring the
hostname.
Tested in x86 native and WOW64 on XP and 2k8r2 respectively.
This is a good option for those of us needing to leave persistent
binaries/payloads on hosts for long periods. Even if the hostname
resolves to a malicious party attempting to steal our hard earned
session, they'd be hard pressed to crypt the payload with the
appropriate RC4 pass. So long as we control the NS and records, the
hardenned shellcode should provide a better night's sleep if running
shells over the WAN. Changing the RC4 password string in the
shellcode and build.py should reduce the chances of recovery by RE.
Next step will likely be to start generating elipses for ECDH SSL
in meterpreter sessions and passing them with stage2 through the
RC4 socket. If P is 768-1024 the process is relatively quick, but
we may want to precompute a few defaults as well to have 2048+.
The HttpOpenRequest function from WinINet requires the
INTERNET_FLAG_KEEP_CONNECTION flag to communicate through an
authenticated proxy.
From MSDN ( http://tinyurl.com/chwt86j ):
"Uses keep-alive semantics, if available, for the connection. This
flag is required for Microsoft Network (MSN), NT LAN Manager (NTLM),
and other types of authentication."
Without this flag, the HTTP stager will fail when faced with a proxy
that requires authentication. The Windows HTTPS stager does not have
this problem.
For HTTP Meterpreter to communicate through an authenticated proxy a
separate patch will need to be made to the Meterpreter source code.
This is at line 1125 of source/common/core.c in the Meterpreter source
code.
My motivation for this request is for windows/dllinject/reverse_http
to download a DLL even when faced with an authenticated proxy. These
changes accomplish this.
Test environment:
I staged a SmoothWall device with the Advanced Proxy Web Add-on. I
enabled Integrated Windows Authentication with a W2K3 DC. I verified
the HTTP stager authenticated to and communicated through the proxy
by watching the proxy access.log
Was seeing this in framework.log:
[w(0)] core: The module php/meterpreter/bind_tcp is ambiguous with
php/meterpreter/bind_tcp.
Added handler_type_alias based on windows/bind_ipv6_tcp stager.
- Adds a call to mprotect(2) to the reverse and bind stagers
- Adds accurate source for some other linux shellcode, including some
comments to make it more maintainable
- Adds tools/module_payload.rb for listing all payloads for each exploit
in a greppable format. Makes it easy to find out if a payload change
causes a payload to no longer be compatible with a given exploit.
- Missing from this commit is source for reverse_ipv6_tcp
Tested with and without AES, works as advertised. Set an AESPassword,
get encryptification. Score.
Squashed commit of the following:
commit cca6c5c36c
Author: Michael Schierl <schierlm@gmx.de>
Date: Wed Apr 4 00:45:24 2012 +0200
Do not break other architectures
even when using `setg AESPassword`
commit 422d1e341b
Author: Michael Schierl <schierlm@gmx.de>
Date: Tue Apr 3 21:50:42 2012 +0200
binaries
commit 27368b5675
Author: Michael Schierl <schierlm@gmx.de>
Date: Tue Apr 3 21:49:10 2012 +0200
Add AES support to Java stager
This is compatible to the AES mode of the JavaPayload project.
I'm pretty sure the way I did it in the handlers (Rex::Socket::tcp_socket_pair())
is not the supposed way, but it works :-)
James Lee