GHSA-mh8g-hprg-8363 Hard-Coded Key Used For Remember-me Token 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 The security configuration in `etc/security/mh_default_org.xml` enables a remember-me cookie based on a hash created from the username, password, and an additional system key. Opencast has hard-coded this system key in the large XML file and never mentions to change this, basically ensuring that all systems use the same key: ```xml ``` This means that an attacker getting access to a remember-me token for one server can get access to all servers which allow log-in using the same credentials without ever needing the credentials. For example, a remember-me token obtained from develop.opencast.org can be used on stable.opencast.org without actually knowing the log-in credentials. Such an attack will usually not work on different installations – assuming that safe, unique passwords are used – but it is basically guaranteed to work to get access to all machines of one cluster if a token from one machine is compromised. Patches This problem is fixed in Opencast 7.6 and Opencast 8.1 Workarounds We strongly recommend updating to the patched version. Still, as a workaround for older versions, in `etc/security/mh_default_org.xml`, set a custom key for each server: ```xml ``` References • Relevant lines in the security configuration • Spring Security Remember-Me Authentication Documentation 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] Thanks Thanks to @LukasKalbertodt for reporting the issue.