SEC Consult Vulnerability Lab Security Advisory < 20180423-0 >
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              title: Multiple Stored XSS Vulnerabilities
            product: WSO2 Carbon, WSO2 Dashboard Server
 vulnerable version: WSO2 Identity Server 5.3.0
      fixed version: WSO2 Identity Server 5.5.0
         CVE number: CVE-2018-8716
             impact: high
           homepage: https://wso2.com/products/dashboard
              found: 2017-12-13
                 by: W. Schober (Office Vienna)
                     SEC Consult Vulnerability Lab

                     An integrated part of SEC Consult
                     Europe | Asia | North America

                     https://www.sec-consult.com

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Vendor description:
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"WSO2 Carbon redefines middleware by providing an integrated and componentized
middleware platform that adapts to the specific needs of any enterprise
IT project - on premise or in the cloud.
100% open source and standards-based, WSO2 Carbon enables developers to rapidly
orchestrate business processes, compose applications and develop services using
WSO2 Developer Studio and a broad range of business and technical services that
integrate with legacy, packaged and SaaS applications.
The lean, complete, OSGi-based platform includes more than 175 components – OSGi
bundles or Carbon features. The WSO2 Carbon core framework functions as
“Eclipse for servers” and includes common capabilities shared by all WSO2
products, such as built-in registry, user management, transports, security,
logging, clustering, caching and throttling services, co-ordination, and a
GUI framework."

Source: https://wso2.com/products/carbon/

"The WSO2 Dashboard Server (formerly WSO2 User Engagement Server) helps to
rapidly create visually appealing and engaging web components such as
dashboards, and gadgets, and unlocking data for business intelligence and
monitoring. With the host of capabilities that Dashboard Server provides
out-of-the-box, going from data to screen has never been easier."

Source: https://wso2.com/products/dashboard-server/


Business recommendation:
------------------------
SEC Consult recommends to perform a thorough security review conducted by
security professionals to identify and resolve all security issues.


Vulnerability overview/description:
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1) Stored Cross-Site Scripting in WSO2 Dashboard (CVE-2018-8716)
The dashboard is used by the end-users to manage their accounts, change passwords,
alter their profiles, or change certain settings. An attacker is able to inject
arbitrary JavaScript payloads into various textboxes (username, home address,
lastname, firstname, etc).

The payloads are permanently stored in the dashboard and triggered every time the
dashboard is visited. The payload is also potentially triggered in the carbon
part of WSO2, which means that an attacker would be able to inject payloads
from the front-end application into a middleware application, which is not
accessible from the internet and attack administrators.

2) Stored Cross-Site Scripting in WSO2 Carbon
The carbon UI offers a feature to add multiple BPS-Worker Hosts. In the worker
host URL an arbitrary JavaScript payload can be injected and permanently stored
in the web application.


Proof of concept:
-----------------
1) Stored Cross-Site Scripting in WS02 Dashboard
The following input fields are vulnerable and JavaScript payloads can be directly
injected:
- Firstname
- Lastname
- Username
- Address

It is suspected, that all user inputs are returned unfiltered in all server responses.

2) Stored Cross-Site Scripting in WSO2 Carbon
To demonstrate the vulnerability, it is sufficient to add a new BPS worker and set
the URL to the following payload: "><img src=x onerror=aler(document.cookie)>

Everytime the carbon middleware application is accessed, the payload is triggered.


Vulnerable / tested versions:
-----------------------------
The following version has been tested which was the most recent version
at the time of discovery:

* WSO2IS 5.3.0


Vendor contact timeline:
------------------------
2018-01-25: Contacting vendor through security@wso2.com
2018-02-08: Asking for status update. Vendor responds, that they are
            still investigating the issue.
2018-02-21: Vendor responds with release date and further details
            concerning the nature of the vulnerabilities. The XSS in the
            Carbon component was a duplicate and should be already fixed.
            Concerning the XSS in the dashboard a fix is implemented
            and will be rolled out with the release of WSO2 Identity
            Server 5.5.0.
2018-03-14: Requesting CVE from Mitre for the stored XSS in the Dashboard.
2018-03-15: Mitre assigned CVE-2018-8716.
2018-03-26: Vendor informed us, that the final release of the updated
            software will be on 5th of April.
2018-04-23: Public Release


Solution:
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Update WSO2 Identity Server to 5.5.0


Workaround:
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No workaround available


Advisory URL:
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https://www.sec-consult.com/en/vulnerability-lab/advisories/index.html