Title: ====== Skype Community - Mail Encoding Web Vulnerability #2 Date: ===== 2012-11-21 References: =========== http://www.vulnerability-lab.com/get_content.php?id=719 VL-ID: ===== 719 Common Vulnerability Scoring System: ==================================== 4 Introduction: ============= Skype is a proprietary voice-over-Internet Protocol service and software application originally created in 2003 by Swedish entrepreneur Niklas Zennström and his Danish partner Janus Friis. It has been owned by Microsoft since 2011. The service allows users to communicate with peers by voice, video, and instant messaging over the Internet. Phone calls may be placed to recipients on the traditional telephone networks. Calls to other users within the Skype service are free of charge, while calls to landline telephones and mobile phones are charged via a debit-based user account system. Skype has also become popular for its additional features, including file transfer, and videoconferencing. Competitors include SIP and H.323-based services, such as Linphone, as well as the Google Talk service, Mumble and Hall.com. Skype has 663 million registered users as of September 2011. The network is operated by Microsoft, which has its Skype division headquarters in Luxembourg. Most of the development team and 44% of the overall employees of the division are situated in Tallinn and Tartu, Estonia. Unlike most other VoIP services, Skype is a hybrid peer-to-peer and client–server system. It makes use of background processing on computers running Skype software. Skype`s original proposed name (Sky Peer-to-Peer) reflects this fact. Some network administrators have banned Skype on corporate, government, home, and education networks, citing reasons such as inappropriate usage of resources, excessive bandwidth usage, and security concerns. (Copy of the Vendor Homepage: http://en.wikipedia.org/wiki/Skype) Abstract: ========= The Vulnerability Laboratory Research Team discovered a filter & mail encoding vulnerability in the official Skype Community Website Application. Report-Timeline: ================ 2012-10-08: Researcher Notification & Coordination 2012-10-10: Vendor Notification 2012-10-12: Vendor Response/Feedback 2012-11-18: Vendor Fix/Patch 2012-11-21: Public or Non-Public Disclosure Status: ======== Published Affected Products: ================== Microsoft Product: Skype Community - Lithium Forums 2012 Q3 Exploitation-Technique: ======================= Remote Severity: ========= High Details: ======== A persistent input validation vulnerability is detected in the official Skype Community Website Application. The vulnerability is located in the update post form with the unsanitized username in send mails. Attackers can inject malicious persistent script code on application side of the skype skype community. The vulnerability is located in the filter function of the username when skype community is processing to send a not parsed update mail. Remote attacker with low privileged application user accounts can change the username values to malicious persistent script code via POST. The result in a persistent script code inject via noreply@skype.net. Successful exploitation of the vulnerability result in persistent phishing attacks, persistent session hijacking or mail context manipulation via persistent inject. Vulnerable Section(s): [+] Skype Community - (Forums) Vulnerable Module(s): [+] Notification Mail Vulnerable Parameter(s): [+] Username Affected Section(s): [+] Update Mail - Filter / Output Listing Proof of Concept: ================= The vulnerability can be exploited by remote attackers with low privileged application user account and with low or medium required user inter action. For demonstration or reproduce ... Skype Support Network Subscription: 1 Update: Betreff: Skype is Hacked ! Win32.Trojan.Agent.Gen schleicht sich durch die Accounts
Betreff: Skype Support Network Subscription: 1 Update: Betreff: Skype is Hacked ! Win32.Trojan.Agent.Gen schleicht sich durch die Accounts
Von: Community Mailer
Datum: 06.10.2012 16:04
An: rm01x

Skype Support Network Subscription: 1 Update: Betreff: Skype is Hacked ! Win32.Trojan.Agent.Gen schleicht sich durch die Accounts

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Solution: ========= The vulnerability can be patched by parsing the context with the lithium api request of the community application formular. Risk: ===== The security risk of the filter & mail encoding vulnerability is estimated as medium(+)|(-)high. Credits: ======== Vulnerability Laboratory [Research Team] - Benjamin Kunz Mejri (bkm@vulnerability-lab.com) Disclaimer: =========== The information provided in this advisory is provided as it is without any warranty. Vulnerability-Lab disclaims all warranties, either expressed or implied, including the warranties of merchantability and capability for a particular purpose. Vulnerability- Lab or its suppliers are not liable in any case of damage, including direct, indirect, incidental, consequential loss of business profits or special damages, even if Vulnerability-Lab or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply. We do not approve or encourage anybody to break any vendor licenses, policies, deface websites, hack into databases or trade with fraud/stolen material. Domains: www.vulnerability-lab.com - www.vuln-lab.com - www.vulnerability-lab.com/register Contact: admin@vulnerability-lab.com - support@vulnerability-lab.com - research@vulnerability-lab.com Section: video.vulnerability-lab.com - forum.vulnerability-lab.com - news.vulnerability-lab.com Social: twitter.com/#!/vuln_lab - facebook.com/VulnerabilityLab - youtube.com/user/vulnerability0lab Feeds: vulnerability-lab.com/rss/rss.php - vulnerability-lab.com/rss/rss_upcoming.php - vulnerability-lab.com/rss/rss_news.php Any modified copy or reproduction, including partially usages, of this file requires authorization from Vulnerability Laboratory. Permission to electronically redistribute this alert in its unmodified form is granted. All other rights, including the use of other media, are reserved by Vulnerability-Lab Research Team or its suppliers. All pictures, texts, advisories, sourcecode, videos and other information on this website is trademark of vulnerability-lab team & the specific authors or managers. To record, list (feed), modify, use or edit our material contact (admin@vulnerability-lab.com or support@vulnerability-lab.com) to get a permission. Copyright © 2012 | Vulnerability Laboratory -- VULNERABILITY RESEARCH LABORATORY LABORATORY RESEARCH TEAM CONTACT: research@vulnerability-lab.com