2020-06-12 21:55:34
apache
PUBLISHED
In Karaf, JMX authentication takes place using JAAS and authorization takes place using ACL files. By default, only an "admin" can actually invoke on an MBean. However there is a vulnerability there for someone who is not an admin, but has a "viewer" role. In the etc/jmx.acl.cfg, such as role can call get*. Its possible to authenticate as a viewer role + invokes on the MLet getMBeansFromURL method, which goes off to a remote server to fetch the desired MBean, which is then registered in Karaf. At this point the attack fails as "viewer" doesnt have the permission to invoke on the MBean. Still, it could act as a SSRF style attack and also it essentially allows a "viewer" role to pollute the MBean registry, which is a kind of privilege escalation. The vulnerability is low as its possible to add a ACL to limit access. Users should update to Apache Karaf 4.2.9 or newer.