An issue was discovered in Zammad 3.0 through 3.2. The WebSocket server crashes when messages in non-JSON format are sent by an attacker. The message format is not properly checked and parsing errors not handled. This leads to a crash of the service process.

An issue was discovered in Zammad 3.0 through 3.2. It does not prevent caching of confidential data within browser memory. An attacker who either remotely compromises or obtains physical access to a user's workstation can browse the browser cache contents and obtain sensitive information. The attacker does not need to be authenticated with the application to view this information, as it would be available via the browser cache.

An issue was discovered in Zammad 3.0 through 3.2. It allows for users to view ticket customer details associated with specific customers. However, the application does not properly implement access controls related to this functionality. As such, users of one company are able to access ticket data from other companies. Due to the multi-tenant nature of this application, users who can access ticket details from one organization to the next allows for users to exfiltrate potentially sensitive data of other companies.

An XSS issue was discovered in Zammad 3.0 through 3.2. Malicious code can be provided by a low-privileged user through the Ticket functionality in Zammad. The malicious JavaScript will execute within the browser of any user who opens the ticket or has the ticket within the Toolbar.

An XSS issue was discovered in Zammad 3.0 through 3.2. Malicious code can be provided by a low-privileged user through the File Upload functionality in Zammad. The malicious JavaScript will execute within the browser of any user who opens a specially crafted link to the uploaded file with an active Zammad session.

An XSS issue was discovered in Zammad 3.0 through 3.2. Malicious code can be provided by a low-privileged user through the Email functionality. The malicious JavaScript will execute within the browser of any user who opens the Ticket with the Article created from that Email.

An issue was discovered in Zammad 3.0 through 3.2. It returns source code of static resources when submitting an OPTIONS request, rather than a GET request. Disclosure of source code allows for an attacker to formulate more precise attacks. Source code was disclosed for the file 404.html (/zammad/public/404.html)

An issue was discovered in Zammad 3.0 through 3.2. It may respond with verbose error messages that disclose internal application or infrastructure information. This information could aid attackers in successfully exploiting other vulnerabilities.

An issue was discovered in Zammad 3.0 through 3.2. The Forgot Password functionality is implemented in a way that would enable an anonymous user to guess valid user emails. In the current implementation, the application responds differently depending on whether the input supplied was recognized as associated with a valid user. This behavior could be used as part of a two-stage automated attack. During the first stage, an attacker would iterate through a list of account names to determine which correspond to valid accounts. During the second stage, the attacker would use a list of common passwords to attempt to brute force credentials for accounts that were recognized by the system in the first stage.

An issue was discovered in Zammad 3.0 through 3.2. After authentication, it transmits sensitive information to the user that may be compromised and used by an attacker to gain unauthorized access. Hashed passwords are returned to the user when visiting a certain URL.