SquidClamav URL Parsing DoS Vulnerability

# SPDX-FileCopyrightText: 2012 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:darold:squidclamav";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.103568");
  script_cve_id("CVE-2012-3501");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_version("2024-06-27T05:05:29+0000");

  script_name("SquidClamav URL Parsing DoS Vulnerability");

  script_xref(name:"URL", value:"http://www.securityfocus.com/bid/54663");

  script_tag(name:"last_modification", value:"2024-06-27 05:05:29 +0000 (Thu, 27 Jun 2024)");
  script_tag(name:"creation_date", value:"2012-09-17 12:15:00 +0200 (Mon, 17 Sep 2012)");
  script_category(ACT_ATTACK);
  script_tag(name:"qod_type", value:"remote_vul");
  script_family("Denial of Service");
  script_tag(name:"solution_type", value:"VendorFix");
  script_copyright("Copyright (C) 2012 Greenbone AG");
  script_dependencies("gb_SquidClamAv_detect.nasl");
  script_require_ports("Services/www", 80);
  script_mandatory_keys("SquidClamAv/installed");
  script_tag(name:"solution", value:"Vendor updates are available. Please see the references for more
information.");
  script_tag(name:"summary", value:"SquidClamav is prone to a denial of service (DoS) vulnerability.");

  script_tag(name:"impact", value:"An attacker can exploit this issue to cause the daemon to crash,
denying service to legitimate users.");

  script_tag(name:"affected", value:"SquidClamav versions prior to 5.8 and 6.7 are vulnerable.");
  exit(0);
}

include("http_func.inc");
include("host_details.inc");
include("http_keepalive.inc");

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

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

url = dir + "/clwarn.cgi?url=<vuln-test>"; # Patch (https://github.com/darold/squidclamav/commit/5806d10a31183a0b0d18eccc3a3e04e536e2315b) -> my $url = CGI::escapeHTML($cgi->param('url')) || '';
                                           # CGI.pm -> The "<" character becomes "&lt;", ">" becomes "&gt;", "&" becomes "&amp;", and the quote character becomes "&quot;".
                                           # That means that if we found an unescape > or < in the response, host is vulnerable.

if(http_vuln_check(port:port, url:url, pattern:"The requested URL <vuln-test>", extra_check:"contains the virus")) {
  report = http_report_vuln_url(port:port, url:url);
  security_message(port:port, data:report);
  exit(0);
}

exit(99);