Vulnerability Note VU#584958

Macromedia JRun is an application server that works with most popular web servers such as Apache and IIS. Macromedia states that JRun is deployed at over 10,000 organizations worldwide. The JSESSIONID is a string that uniquely identifies a user's session. JSESSIONIDs are generated using a limited character set (0-9) , therefore reducing the search space required for a brute-force attack. According to reports, JRun Server also handles the JSESSIONIDs insecurely potentially allowing an attacker to gain access to an authorized user's session. The insecure handling may involve how JSESSIONIDs are stored in web browser cookies or URLs. However, the specific details are not available at this time.

Exploitation of this vulnerability may allow an attacker to hijack an authenticated user's session allowing the attacker to access sensitive information or execute commands on the server with the privileges of the compromised session.

Apply Patch

In the latest updater increases the security of the JSESSIONID by expanding the character set used for JESSIONIDs to include letters as well as numbers.

It is available for download at:

http://www.macromedia.com/support/jrun/updaters.html.