ProFTPD < 1.3.2b / 1.3.3x < 1.3.3rc2 client-hostname restriction bypass

#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(106752);
  script_version("1.4");
  script_cvs_date("Date: 2019/11/08");

  script_cve_id("CVE-2009-3639");
  script_bugtraq_id(36804);

  script_name(english:"ProFTPD < 1.3.2b / 1.3.3x < 1.3.3rc2 client-hostname restriction bypass");
  script_summary(english:"Checks version of ProFTPD.");

  script_set_attribute(attribute:"synopsis", value:
"The remote FTP server is affected by a Denial of Service
vulnerability.");
  script_set_attribute(attribute:"description", value:
"The remote host is using ProFTPD, a free FTP server for Unix and
Linux.
According to its banner, the version of ProFTPD installed on the
remote host is 1.3.2x prior to 1.3.2b or 1.3.3x prior to 1.3.3rc2 
and is affected by a mitigation bypass vulnerability when
the dNSNameRequired TLS option is enabled.");
  script_set_attribute(attribute:"see_also", value:"http://bugs.proftpd.org/show_bug.cgi?id=3275");
  script_set_attribute(attribute:"solution", value:
"Upgrade to ProFTPD version 1.3.2b / 1.3.3rc2 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(310);

  script_set_attribute(attribute:"vuln_publication_date", value:"2008/08/06");
  script_set_attribute(attribute:"patch_publication_date", value:"2008/10/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/02/12");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:proftpd:proftpd");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"FTP");

  script_copyright(english:"This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ftp_overflow.nasl", "ftpserver_detect_type_nd_version.nasl");
  script_require_keys("ftp/proftpd", "Settings/ParanoidReport");
  script_require_ports("Services/ftp", 21);

  exit(0);
}

include("audit.inc");
include("ftp_func.inc");
include("global_settings.inc");

if (report_paranoia < 2) audit(AUDIT_PARANOID);

port = get_ftp_port(default: 21, broken:TRUE);

app = "ProFTPD";
banner = get_ftp_banner(port:port);
if (!banner) audit(AUDIT_NO_BANNER, port);
if (app >!< banner) audit(AUDIT_NOT_DETECT, app, port);

matches = pregmatch(string:banner, pattern:"ProFTPD ([0-9a-z.]+) ");
if (isnull(matches)) audit(AUDIT_SERVICE_VER_FAIL, app, port);
version = matches[1];

if (version =~ '^1(\\.3)?$') audit(AUDIT_VER_NOT_GRANULAR, app, version);

if (
  version =~ "^0($|\.)" ||
  version =~ "^1\.[0-2]($|\.)" ||
  version =~ "^1\.3\.1($|[^0-9])" ||
  version =~ "^1\.3\.2(rc[1-4]|a)?($|[^0-9b-z])"||
  version =~ "^1\.3\.3(rc1)?($|[^0-9a-z])"
)
{
  report =
    '\n  Version source    : ' + chomp(banner) +
    '\n  Installed version : ' + version +
    '\n  Fixed version     : 1.3.2b / 1.3.3rc2\n';
  security_report_v4(severity:SECURITY_WARNING, port:port, extra:report);
  exit(0);
}
else audit(AUDIT_LISTEN_NOT_VULN, app, port, version);