Ruby WEBrick Terminal Escape Sequence in Logs Command Injection Vulnerability

# SPDX-FileCopyrightText: 2010 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

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.100445");
  script_version("2023-08-04T05:06:23+0000");
  script_tag(name:"last_modification", value:"2023-08-04 05:06:23 +0000 (Fri, 04 Aug 2023)");
  script_tag(name:"creation_date", value:"2010-01-13 11:20:27 +0100 (Wed, 13 Jan 2010)");
  script_cve_id("CVE-2009-4492");
  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_name("Ruby WEBrick Terminal Escape Sequence in Logs Command Injection Vulnerability");

  script_xref(name:"URL", value:"http://www.securityfocus.com/bid/37710");
  script_xref(name:"URL", value:"http://www.ruby-lang.org/en/news/2010/01/10/webrick-escape-sequence-injection/");
  script_xref(name:"URL", value:"http://www.securityfocus.com/archive/1/508830");

  script_category(ACT_GATHER_INFO);
  script_family("Web Servers");
  script_copyright("Copyright (C) 2010 Greenbone AG");
  script_dependencies("gb_get_http_banner.nasl", "httpver.nasl");
  script_require_ports("Services/www", 8080);
  script_mandatory_keys("WEBrick/banner");

  script_tag(name:"solution", value:"Updates are available. Please see the references for details.");

  script_tag(name:"summary", value:"Ruby WEBrick is prone to a command-injection vulnerability because it
  fails to adequately sanitize user-supplied input in log files.");

  script_tag(name:"impact", value:"Attackers can exploit this issue to execute arbitrary commands in
  a terminal.");

  script_tag(name:"affected", value:"Versions *prior to* the following are affected:

  Ruby 1.8.6 patchlevel 388 Ruby 1.8.7 patchlevel 249 Ruby 1.9.1 patchlevel 378");

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

  exit(0);
}

include("http_func.inc");
include("port_service_func.inc");
include("version_func.inc");

port = http_get_port(default:8080);

banner = http_get_remote_headers(port: port);

if(!banner && "Server: WEBrick" >!< banner) exit(0);

if(!matches = eregmatch(pattern: "Server: WEBrick/[0-9.]+ \(Ruby/([0-9.]+)/([0-9]{4}-[0-9]{2}-[0-9]{2})\)", string: banner))exit(0);
if(isnull(matches[1]) || isnull(matches[2]))exit(0);

release = matches[1];
release_date = matches[2];

if(version_is_equal(version: release, test_version: "1.8.6") ||
   version_is_equal(version: release, test_version: "1.8.7") ||
   version_is_equal(version: release, test_version: "1.9.1")) {

  rdate = split(release_date, sep: "-", keep: FALSE);
  if(isnull(rdate[0]) || isnull(rdate[1]) || isnull(rdate[2]))exit(0);

  if(int(rdate[0]) < 2010) {
    VULN = TRUE;
  }
  else if(int(rdate[0]) == 2010 && int(rdate[1]) == 1 && int(rdate[2]) < 10) {
    VULN = TRUE;
  }

  if(VULN) {
    report = report_fixed_ver(installed_version:release, fixed_version:"1.8.6/1.8.7/1.9.1");
    security_message(port:port, data:report);
    exit(0);
  }
}

exit(99);