============================================= INTERNET SECURITY AUDITORS ALERT 2010-009 - Original release date: August 30th, 2010 - Last revised: September 21st, 2010 - Discovered by: Vicente Aguilera Diaz - Severity: 4.3/10 (CVSSv2 Base Scored) ============================================= I. VULNERABILITY ------------------------- Reflected XSS in the login process of the Atmail WebMail < v6.1.9 II. BACKGROUND ------------------------- Atmail allows users to access IMAP Mailboxes of any server of your choice. The software provides a comprehensive email-suite for accessing user mailboxes, and provides an inbuilt Calendar and Addressbook features. The WebMail Client of Atmail supports any existing IMAP server running under Unix/Linux or Windows systems. III. DESCRIPTION ------------------------- Has been detected a reflected XSS vulnerability in the login process of the Atmail WebMail, that allows the execution of arbitrary HTML/script code to be executed in the context of the victim user's browser. The code injection is done through the "MailType" parameter, and can be exploited without a user account in the WebMail. Moreover, the login request may be made by the HTTP GET method (by default, HTTP POST method is used), so this facilitates the exploitation of the vulnerability. IV. PROOF OF CONCEPT ------------------------- === Original request: POST /index.php/mail/auth/processlogin HTTP/1.1 Host: <atmail_host> ... emailName=<emailName>&emailDomain=<emailDomain>&cssStyle=original&email= <email>password=<password>&requestedServer=&MailType=IMAP === Malicious request - Example 1: POST /index.php/mail/auth/processlogin HTTP/1.1 Host: <atmail_host> ... emailName=<emailName>&emailDomain=<emailDomain>&cssStyle=original&email= <email>password=<password>&requestedServer=&MailType=<script>alert(docum ent.cookie);</script> === Malicious request - Example 2: GET /index.php/mail/auth/processlogin?emailName=<emailName>&emailDomain=<ema ilDomain>&cssStyle=original&email=<email>password=<password>&requestedSe rver=&MailType=<script>alert(document.cookie);</script> HTTP/1.1 V. BUSINESS IMPACT ------------------------- An attacker can execute arbitrary HTML or script code in a targeted user's browser, this can leverage to steal sensitive information as user credentials, personal data, etc. VI. SYSTEMS AFFECTED ------------------------- Tested in Atmail 6.1.9. Other versions may be affected too. VII. SOLUTION ------------------------- Upgrade to version 6.2.0 VIII. REFERENCES ------------------------- http://www.atmail.com http://www.isecauditors.com IX. CREDITS ------------------------- This vulnerability has been discovered by Vicente Aguilera Diaz (vaguilera (at) isecauditors (dot) com). X. REVISION HISTORY ------------------------- August 30, 2010: Initial release September 21, 2010: Last revision XI. DISCLOSURE TIMELINE ------------------------- August 30, 2010: Discovered by Internet Security Auditors August 31, 2010: Atmail contacted including PoC. Response about the scheduled correction. September 2, 2010: Published version 6.2.0 that includes this patch. September 21, 2010: Advisory sent to public 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.