Sametime is impacted by lack of clickjacking protection in Outlook add-in. The application is not implementing appropriate protections in order to protect users from clickjacking attacks.

This vulnerability allows users to execute a clickjacking attack in the meeting's chat.

The vulnerability was discovered within the “FaviconService”. The service takes a base64-encoded URL which is then requested by the webserver. We assume this service is used by the “meetings”-function where users can specify an external URL where the online meeting will take place.

Users are able to read group conversations without actively taking part in them. Next to one to one conversations, users are able to start group conversations with multiple users. It was found possible to obtain the contents of these group conversations without being part of it. This could lead to information leakage where confidential information discussed in private groups is read by other users without the users knowledge.

Information leakage occurs when a website reveals information that could aid an attacker to further exploit the system. This information may or may not be sensitive and does not automatically mean a breach is likely to occur. Overall, any information that could be used for an attack should be limited whenever possible.

User SID can be modified resulting in an Arbitrary File Upload or deletion of directories causing a Denial of Service. When interacting in a normal matter with the Sametime chat application, users hold a cookie containing their session ID (SID). This value is also used when sending chat messages, receiving notifications and/or transferring files.