ZITADEL uses HTML for emails and renders certain information such as usernames dynamically. That information can be entered by users or administrators. Due to a missing output sanitization, these emails could include malicious code. This may potentially lead to a threat where an attacker, without privileges, could send out altered notifications that are part of the registration processes. An attacker could create a malicious link, where the injected code would …
ZITADEL administrators can enable a setting called "Ignoring unknown usernames" which helps mitigate attacks that try to guess/enumerate usernames. If enabled, ZITADEL will show the password prompt even if the user doesn't exist and report "Username or Password invalid". Due to a implementation change to prevent deadlocks calling the database, the flag would not be correctly respected in all cases and an attacker would gain information if an account exist …
ZITADEL provides users the ability to list all user sessions of the current user agent (browser) by API and in the Console UI. Due to a missing check, user sessions without that information (e.g. when created though the session service) were incorrectly listed exposing potentially other user's sessions. Note that the Login UI was never affected and there was no possibility to take over such a session.
In case ZITADEL could not connect to the database, connection information including db name, username and db host name could be returned to the user.
ZITADEL provides users the possibility to use Time-based One-Time-Password (TOTP) and One-Time-Password (OTP) through SMS and Email. While ZITADEL already gives administrators the option to define a Lockout Policy with a maximum amount of failed password check attempts, there was no such mechanism for (T)OTP checks.
ZITADEL users can upload their own avatar image and various image types are allowed. Due to a missing check, an attacker could upload HTML and pretend it is an image to gain access to the victim's account in certain scenarios. A possible victim would need to directly open the supposed image in the browser, where a session in ZITADEL needs to be active for this exploit to work. The exploit …
Under certain circumstances an action could set reserved claims managed by ZITADEL. For example it would be possible to set the claim urn:zitadel:iam:user:resourceowner:name {"urn:zitadel:iam:user:resourceowner:name": "ACME"} if it was not set by ZITADEL itself. To compensate for this we introduced a protection that does prevent actions from changing claims that start with urn:zitadel:iam
ZITADEL uses Go templates to render the login UI. Due to a improper use of the text/template instead of the html/template package, the Login UI did not sanitize input parameters. An attacker could create a malicious link, where he injected code which would be rendered as part of the login screen. While it was possible to inject HTML including javascript, the execution of such scripts would be prevented by the …
Impact ZITADEL uses a cookie to identify the user agent (browser) and its user sessions. Although the cookie was handled according to best practices, it was accessible on subdomains of the ZITADEL instance. An attacker could take advantage of this and provide a malicious link hosted on the subdomain to the user to gain access to the victim’s account in certain scenarios. A possible victim would need to login through …