Vulnerabilities > CVE-2016-9681 - Cross-site Scripting vulnerability in S9Y Serendipity

047910
CVSS 5.4 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
LOW
Integrity impact
LOW
Availability impact
NONE
network
low complexity
s9y
CWE-79
nessus

Summary

Multiple cross-site scripting (XSS) vulnerabilities in Serendipity before 2.0.5 allow remote authenticated users to inject arbitrary web script or HTML via a category or directory name.

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Cross Site Scripting through Log Files
    An attacker may leverage a system weakness where logs are susceptible to log injection to insert scripts into the system's logs. If these logs are later viewed by an administrator through a thin administrative interface and the log data is not properly HTML encoded before being written to the page, the attackers' scripts stored in the log will be executed in the administrative interface with potentially serious consequences. This attack pattern is really a combination of two other attack patterns: log injection and stored cross site scripting.
  • Embedding Scripts in Non-Script Elements
    This attack is a form of Cross-Site Scripting (XSS) where malicious scripts are embedded in elements that are not expected to host scripts such as image tags (<img>), comments in XML documents (< !-CDATA->), etc. These tags may not be subject to the same input validation, output validation, and other content filtering and checking routines, so this can create an opportunity for an attacker to tunnel through the application's elements and launch a XSS attack through other elements. As with all remote attacks, it is important to differentiate the ability to launch an attack (such as probing an internal network for unpatched servers) and the ability of the remote attacker to collect and interpret the output of said attack.
  • Embedding Scripts within Scripts
    An attack of this type exploits a programs' vulnerabilities that are brought on by allowing remote hosts to execute scripts. The attacker leverages this capability to execute scripts to execute his/her own script by embedding it within other scripts that the target software is likely to execute. The attacker must have the ability to inject script into script that is likely to be executed. If this is done, then the attacker can potentially launch a variety of probes and attacks against the web server's local environment, in many cases the so-called DMZ, back end resources the web server can communicate with, and other hosts. With the proliferation of intermediaries, such as Web App Firewalls, network devices, and even printers having JVMs and Web servers, there are many locales where an attacker can inject malicious scripts. Since this attack pattern defines scripts within scripts, there are likely privileges to execute said attack on the host. Of course, these attacks are not solely limited to the server side, client side scripts like Ajax and client side JavaScript can contain malicious scripts as well. In general all that is required is for there to be sufficient privileges to execute a script, but not protected against writing.
  • Cross-Site Scripting in Error Pages
    An attacker distributes a link (or possibly some other query structure) with a request to a third party web server that is malformed and also contains a block of exploit code in order to have the exploit become live code in the resulting error page. When the third party web server receives the crafted request and notes the error it then creates an error message that echoes the malformed message, including the exploit. Doing this converts the exploit portion of the message into to valid language elements that are executed by the viewing browser. When a victim executes the query provided by the attacker the infected error message error message is returned including the exploit code which then runs in the victim's browser. XSS can result in execution of code as well as data leakage (e.g. session cookies can be sent to the attacker). This type of attack is especially dangerous since the exploit appears to come from the third party web server, who the victim may trust and hence be more vulnerable to deception.
  • Cross-Site Scripting Using Alternate Syntax
    The attacker uses alternate forms of keywords or commands that result in the same action as the primary form but which may not be caught by filters. For example, many keywords are processed in a case insensitive manner. If the site's web filtering algorithm does not convert all tags into a consistent case before the comparison with forbidden keywords it is possible to bypass filters (e.g., incomplete black lists) by using an alternate case structure. For example, the "script" tag using the alternate forms of "Script" or "ScRiPt" may bypass filters where "script" is the only form tested. Other variants using different syntax representations are also possible as well as using pollution meta-characters or entities that are eventually ignored by the rendering engine. The attack can result in the execution of otherwise prohibited functionality.

Nessus

NASL familyCGI abuses
NASL idSERENDIPITY_211.NASL
descriptionAccording to its banner, the version of Serendipity running on the remote host is prior to 2.1.1. It is, therefore, affected by multiple vulnerabilities : - A stored cross-site scripting (XSS) vulnerability exists in the templates/2k11/admin/category.inc.tpl script due to improper validation of the category and directory names before returning the input to users. An authenticated, remote attacker can exploit this, via a specially crafted request, to execute arbitrary script code in a user
last seen2020-06-01
modified2020-06-02
plugin id100789
published2017-06-14
reporterThis script is Copyright (C) 2017-2018 Tenable Network Security, Inc.
sourcehttps://www.tenable.com/plugins/nessus/100789
titleSerendipity < 2.1.1 Multiple Vulnerabilities
code
#
# (C) Tenable Network Security, Inc.
#


include("compat.inc");

if (description) {
  script_id(100789);
  script_version("1.4");
  script_cvs_date("Date: 2018/07/30 11:55:11");

  script_cve_id(
    "CVE-2016-9681",
    "CVE-2016-10082",
    "CVE-2017-5474",
    "CVE-2017-5475",
    "CVE-2017-5476"
  );
  script_bugtraq_id(
    95095,
    95165,
    95652,
    95656,
    95659
  );

  script_name(english:"Serendipity < 2.1.1 Multiple Vulnerabilities");
  script_summary(english:"Checks the version of Serendipity.");

  script_set_attribute(attribute:"synopsis", value:
"The remote web server contains a PHP application that is affected by
multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"According to its banner, the version of Serendipity running on the
remote host is prior to 2.1.1. It is, therefore, affected by multiple
vulnerabilities :

  - A stored cross-site scripting (XSS) vulnerability exists
    in the templates/2k11/admin/category.inc.tpl script due
    to improper validation of the category and directory
    names before returning the input to users. An
    authenticated, remote attacker can exploit this, via a
    specially crafted request, to execute arbitrary script
    code in a user's browser session. (CVE-2016-9681)

  - A local file inclusion flaw exists in the
    include/functions_installer.inc.php script due to
    improper sanitization of user supplied-input to the
    'dbType' POST parameter. An unauthenticated, remote
    attacker can exploit this, via a specially crafted
    request that uses absolute paths, to include files on
    the targeted host, resulting in the disclosure of file
    contents or the possible execution of files as PHP
    scripts. (CVE-2016-10082)

  - A cross-site redirection vulnerability exists in the
    comment.php script due to improper validation of the
    HTTP referer header. An unauthenticated, remote attacker
    can exploit this, via a specially crafted link, to
    redirect an unsuspecting user from a legitimate website
    to a website of the attacker's choosing, which could
    then be used to conduct further attacks.
    (CVE-2017-5474)

  - A cross-site request forgery (XSRF) vulnerability exists
    in comment.php due to not requiring multiple steps,
    explicit confirmation, or a unique token when performing
    certain sensitive actions. An unauthenticated, remote
    attacker can exploit this, by convincing a user to
    follow a specially crafted link, to cause the deletion
    of arbitrary comments. (CVE-2017-5475)

  - A cross-site request forgery (XSRF) vulnerability exists
    in unspecified scripts due to not requiring multiple
    steps, explicit confirmation, or a unique token when
    performing certain sensitive actions. An
    unauthenticated, remote attacker can exploit this, by
    convincing a user to follow a specially crafted link, to
    cause the installation of event or sidebar plugins.
    (CVE-2017-5476)");
  script_set_attribute(attribute:"see_also", value:"https://github.com/s9y/Serendipity/issues/433");
  script_set_attribute(attribute:"see_also", value:"https://github.com/s9y/Serendipity/issues/439");
  # https://github.com/s9y/Serendipity/commit/e2a665e13b7de82a71c9bbb77575d15131b722be
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?98bd3703");
  # https://github.com/s9y/Serendipity/commit/6285933470bab2923e4573b5d54ba9a32629b0cd
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?93a3f574");
  script_set_attribute(attribute:"see_also", value:"https://blog.s9y.org/archives/274-Serendipity-2.1.1-released.html");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Serendipity version 2.1.1 or later." );
  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_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No exploit is required");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2016/11/28");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/04/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/06/14");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe",value:"cpe:/a:s9y:serendipity");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2017-2018 Tenable Network Security, Inc.");

  script_dependencies("serendipity_detect.nasl");
  script_exclude_keys("Settings/disable_cgi_scanning");
  script_require_ports("Services/www", 80);
  script_require_keys("www/serendipity");

  exit(0);
}

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

app = 'serendipity';
fix = '2.1.1';

get_install_count(app_name:app, exit_if_zero:TRUE);
port = get_http_port(default:80, php:TRUE);

app_info = vcf::get_app_info(app:app, port:port, webapp:TRUE);
vcf::check_granularity(app_info:app_info, sig_segments:3);

constraints = [
    {"max_version" : "2.1.0", "fixed_version" : "2.1.1"  }
];

vcf::check_version_and_report(app_info:app_info, constraints:constraints, severity:SECURITY_HOLE, flags:{xss:TRUE,xsrf:TRUE});