Vulnerabilities > CVE-2017-8569 - Cross-site Scripting vulnerability in Microsoft Sharepoint Server 2016

047910
CVSS 6.5 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
SINGLE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
PARTIAL
network
low complexity
microsoft
CWE-79
nessus

Summary

Microsoft SharePoint Server allows an elevation of privilege vulnerability due to the way that it sanitizes a specially crafted web request to an affected SharePoint server, aka "SharePoint Server XSS Vulnerability".

Vulnerable Configurations

Part Description Count
Application
Microsoft
1

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 familyWindows : Microsoft Bulletins
NASL idSMB_NT_MS17_JUL_OFFICE_SHAREPOINT.NASL
descriptionThe Microsoft SharePoint Server or Project Server installed on the remote Windows host is missing a security update. It is, therefore, affected by multiple vulnerabilities : - A remote code execution vulnerability exists in Microsoft Office due to improper handling of objects in memory. An unauthenticated, remote attacker can exploit this, by convincing a user to visit a specially crafted website or open a specially crafted document, to execute arbitrary code in the context of the current user. (CVE-2017-0243) - A remote code execution vulnerability exists in Microsoft Office due to improper handling of objects in memory. An unauthenticated, remote attacker can exploit this, by convincing a user to visit a specially crafted website or open a specially crafted document, to execute arbitrary code in the context of the current user. (CVE-2017-8501) - A cross-site scripting (XSS) vulnerability exists in Microsoft SharePoint Server due improper validation of user-supplied input in web requests. 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 id101372
published2017-07-11
reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/101372
titleSecurity Update for Microsoft SharePoint Server and Project Server (July 2017)
code
#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(101372);
  script_version("1.12");
  script_cvs_date("Date: 2019/11/12");

  script_cve_id("CVE-2017-0243", "CVE-2017-8501", "CVE-2017-8569");
  script_bugtraq_id(99441, 99446, 99447);
  script_xref(name:"MSKB", value:"3191902");
  script_xref(name:"MSFT", value:"MS17-3191902");
  script_xref(name:"MSKB", value:"3203459");
  script_xref(name:"MSFT", value:"MS17-3203459");
  script_xref(name:"MSKB", value:"3213544");
  script_xref(name:"MSFT", value:"MS17-3213544");
  script_xref(name:"MSKB", value:"3213559");
  script_xref(name:"MSFT", value:"MS17-3213559");
  script_xref(name:"MSKB", value:"3213629");
  script_xref(name:"MSFT", value:"MS17-3213629");

  script_name(english:"Security Update for Microsoft SharePoint Server and Project Server (July 2017)");
  script_summary(english:"Checks the file versions.");

  script_set_attribute(attribute:"synopsis", value:
"An application installed on the remote Windows host is affected by
multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The Microsoft SharePoint Server or Project Server installed on the
remote Windows host is missing a security update. It is, therefore,
affected by multiple vulnerabilities :

  - A remote code execution vulnerability exists in
    Microsoft Office due to improper handling of objects in
    memory. An unauthenticated, remote attacker can exploit
    this, by convincing a user to visit a specially crafted
    website or open a specially crafted document, to
    execute arbitrary code in the context of the current
    user. (CVE-2017-0243)

  - A remote code execution vulnerability exists in
    Microsoft Office due to improper handling of objects in
    memory. An unauthenticated, remote attacker can exploit
    this, by convincing a user to visit a specially crafted
    website or open a specially crafted document, to
    execute arbitrary code in the context of the current
    user. (CVE-2017-8501)

  - A cross-site scripting (XSS) vulnerability exists in
    Microsoft SharePoint Server due improper validation of
    user-supplied input in web requests. An authenticated,
    remote attacker can exploit this, via a specially
    crafted request, to execute arbitrary script code in a
    user's browser session. (CVE-2017-8569)");
  # https://support.microsoft.com/eu-es/help/3191902/descriptionofthesecurityupdateforexcelservicesonsharepointserver2010ju
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?26d330c5");
  # https://support.microsoft.com/eu-es/help/3203459/descriptionofthesecurityupdateforsharepointserver2010july11-2017
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?085f59c5");
  # https://support.microsoft.com/en-us/help/3213544/descriptionofthesecurityupdateforsharepointserver2016july11-2017
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?a76483b3");
  # https://support.microsoft.com/en-us/help/3213559/descriptionofthesecurityupdateforsharepointserver2013july11-2017
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?31828232");
  # https://support.microsoft.com/eu-es/help/3213629/july-11-2017-cumulative-update-for-project-server-2010-kb3213629
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d4c8bed4");
  script_set_attribute(attribute:"solution", value:
"Microsoft has released a set of patches for SharePoint Server 2013
and 2016; Excel Services on SharePoint Server 2010; and Microsoft
Project Server 2010.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/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:"cvss_score_source", value:"CVE-2017-8501");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/07/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/07/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/07/11");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:office");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:project_server");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:microsoft:sharepoint_server");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Windows : Microsoft Bulletins");

  script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("microsoft_sharepoint_installed.nbin", "smb_hotfixes.nasl", "ms_bulletin_checks_possible.nasl", "microsoft_office_compatibility_pack_installed.nbin", "microsoft_project_installed.nbin");
  script_require_keys("SMB/MS_Bulletin_Checks/Possible");
  script_require_ports(139, 445, "Host/patch_management_checks");

  exit(0);
}

include("audit.inc");
include("smb_func.inc");
include("smb_hotfixes.inc");
include("smb_hotfixes_fcheck.inc");
include("smb_reg_query.inc");
include("misc_func.inc");
include("install_func.inc");

get_kb_item_or_exit("SMB/MS_Bulletin_Checks/Possible");

bulletin = "MS17-07";
kbs = make_list(
  '3191902', # Excel Services Microsoft SharePoint Server 2010 Service Pack 2
  '3203459', # Security Update for 2010 Microsoft Business Productivity Servers 
  '3213544', # SharePoint Server 2016
  '3213559', # SharePoint Server 2013
  '3213629'  # Project Server 2010
);

if (get_kb_item("Host/patch_management_checks")) 
hotfix_check_3rd_party(bulletin:bulletin, kbs:kbs, severity:SECURITY_HOLE);

get_kb_item_or_exit("SMB/Registry/Enumerated", exit_code:1);

# Get path information for Windows.
windir = hotfix_get_systemroot();
if (isnull(windir)) exit(1, "Failed to determine the location of %windir%.");

registry_init();

var sps_2016_path, sps_2016_sp, sps_2016_edition;
var sps_2013_path, sps_2013_sp, sps_2013_edition;
var sps_2010_path, sps_2010_sp, sps_2010_edition;

vuln = FALSE;
xss  = FALSE;
port = kb_smb_transport();

installs = get_installs(app_name:"Microsoft SharePoint Server", exit_if_not_found:TRUE);

foreach install (installs[1])
{
  if (install["Product"] == "2016")
  {
    sps_2016_path = install['path'];
    sps_2016_sp = install['SP'];
    sps_2016_edition = install['Edition'];
  }
  else if (install["Product"] == "2013")
  {
    sps_2013_path = install['path'];
    sps_2013_sp = install['SP'];
    sps_2013_edition = install['Edition'];
  }
  else if (install["Product"] == "2010")
  {
    sps_2010_path = install['path'];
    sps_2010_sp = install['SP'];
    sps_2010_edition = install['Edition'];
  }
}

######################################################################
# SharePoint Server 2016
######################################################################
if (sps_2016_path && sps_2016_sp == "0" && sps_2016_edition == "Server")
{
  path = hotfix_append_path(path:sps_2016_path, value:"WebServices\ConversionServices");
  if (hotfix_check_fversion(file:"sword.dll", version:"16.0.4561.1000", min_version:"16.0.0.0", path:path, kb:"3213544", product:"Office SharePoint Server 2016") == HCF_OLDER)
  {
    xss = TRUE;
    vuln = TRUE;
  }
}

######################################################################
# SharePoint Server 2013 SP1
######################################################################
if (sps_2013_path && sps_2013_sp == "1")
{
  if(sps_2013_edition == "Server")
  {
    # Files under <sps_2013_path>\bin
    path = hotfix_append_path(path:sps_2013_path, value:"Bin");
    if (hotfix_check_fversion(file:"xlsrv.dll", version:"15.0.4945.1000", min_version:"15.0.0.0", path:path, kb:"3213559", product:"Office SharePoint Server 2013") == HCF_OLDER)
     vuln = TRUE;
  }
}

######################################################################
# SharePoint Server 2010 SP2
######################################################################
if (sps_2010_path && sps_2010_sp == "2")
{
  path = hotfix_append_path(path:sps_2010_path, value:"Bin");

  # Project Server 2010
  if(get_install_count(app_name:"Microsoft Project Server") > 0)
  {
    if (hotfix_check_fversion(file:"xlsrv.dll", version:"14.0.7183.5000", path:path, kb:"3213629", product:"Microsoft Project Server 2010") == HCF_OLDER)
      vuln = TRUE;
  }

  # 2010 Microsoft Business Productivity Servers 
  ## NB: This will only report a vulnerability if the Galician
  ## language pack has been installed. This is as it should be.
  proof_path = ereg_replace(string:sps_2010_path, pattern:"^(.+)\\14.0\\?$", replace:"\1\OFFICE14\PROOF");
  if (hotfix_check_fversion(file:"mssp3gl.dll", version:"15.0.4569.1503", min_version:"14.0.0.0", path:proof_path, kb:"3203459", product:"SharePoint 2010 for Microsoft Business Productivity Servers") == HCF_OLDER)
    vuln = TRUE;

  if (sps_2010_edition == "Server")
  {
    if (hotfix_check_fversion(file:"xlsrv.dll", version:"14.0.7183.5000", path:path, kb:"3191902", product:"Office SharePoint Server 2010 Excel Services") == HCF_OLDER)
      vuln = TRUE;
  }
}

if (vuln)
{
  # CVE-2017-8569
  if(xss) replace_kb_item(name:'www/'+port+'/XSS', value:TRUE);

  replace_kb_item(name:'SMB/Missing/'+bulletin, value:TRUE);
  hotfix_security_hole();
  hotfix_check_fversion_end();
  exit(0);
}
else
{
  hotfix_check_fversion_end();
  audit(AUDIT_HOST_NOT, 'affected');
}