GHSA-vmm6-w4cf-7f3x Authentication Bypass For Endpoints With Anonymous Access in Opencast

• Maven org.opencastproject:opencast-kernel: < 7.6 → fixed in 7.6 • Maven org.opencastproject:opencast-kernel: >= 8.0, < 8.1 → fixed in 8.1

Impact Using a remember-me cookie with an arbitrary username can cause Opencast to assume proper authentication for that user even if the remember-me cookie was incorrect given that the attacked endpoint also allows anonymous access. This way, an attacker can, for example, fake a remember-me token, assume the identity of the global system administrator and request non-public content from the search service without ever providing any proper authentication. Patches This problem is fixed in Opencast 7.6 and Opencast 8.1 Workarounds As a workaround for older, unpatched versions, disabling remember-me cookies in `etc/security/mh_default_org.xml` will mitigate the problem but will obviously also disable this feature without obvious indication. To deactivate this, remove the following line from the security configuration: ```xml ``` References • Remember-me cookie in the security configuration file For more information If you have any questions or comments about this advisory: • Open an issue in opencast/opencast • For security-relevant information, email us at [email protected]