Apache Software Foundation Karaf

Apache Karaf provides a features deployer, which allows users to "hot deploy" a features XML by dropping the file directly in the deploy folder. The features XML is parsed by XMLInputFactory class. Apache Karaf XMLInputFactory class doesn't contain any mitigation codes against XXE. This is a potential security risk as an user can inject external XML entities in Apache Karaf version prior to 4.1.7 or 4.2.2. It has been fixed in Apache Karaf 4.1.7 and 4.2.2 releases.

Apache Karaf: JDBC JAAS LDAP injection

In Apache Karaf prior to 4.2.0 release, if the sshd service in Karaf is left on so an administrator can manage the running instance, any user with rights to the Karaf console can pivot and read/write any file on the file system to which the Karaf process user has access. This can be locked down a bit by using chroot to change the root directory to protect files outside of the Karaf install directory; it can be further locked down by defining a security manager policy that limits file system access to those directories beneath the Karaf home that are necessary for the system to run. However, this still allows anyone with ssh access to the Karaf process to read and write a large number of files as the Karaf process user.

An issue was discovered in Legion of the Bouncy Castle BC Java 1.65 and 1.66. The OpenBSDBCrypt.checkPassword utility method compared incorrect data when checking the password, allowing incorrect passwords to indicate they were matching with previously hashed ones that were different.

In Apache Karaf version prior to 3.0.9, 4.0.9, 4.1.1, when the webconsole feature is installed in Karaf, it is available at .../system/console and requires authentication to access it. One part of the console is a Gogo shell/console that gives access to the command line console of Karaf via a Web browser, and when navigated to it is available at .../system/console/gogo. Trying to go directly to that URL does require authentication. And optional bundle that some applications use is the Pax Web Extender Whiteboard, it is part of the pax-war feature and perhaps others. When it is installed, the Gogo console becomes available at another URL .../gogo/, and that URL is not secured giving access to the Karaf console to unauthenticated users. A mitigation for the issue is to manually stop/uninstall Gogo plugin bundle that is installed with the webconsole feature, although of course this removes the console from the .../system/console application, not only from the unauthenticated endpoint. One could also stop/uninstall the Pax Web Extender Whiteboard, but other components/applications may require it and so their functionality would be reduced/compromised.

Insecure Java Deserialization in Apache Karaf

Apache Karaf prior to 4.0.8 used the LDAPLoginModule to authenticate users to a directory via LDAP. However, it did not encoding usernames properly and hence was vulnerable to LDAP injection attacks leading to a denial of service.

Apache Karaf kar deployer reads .kar archives and extracts the paths from the "repository/" and "resources/" entries in the zip file. It then writes out the content of these paths to the Karaf repo and resources directories. However, it doesn't do any validation on the paths in the zip file. This means that a malicious user could craft a .kar file with ".." directory names and break out of the directories to write arbitrary content to the filesystem. This is the "Zip-slip" vulnerability - https://snyk.io/research/zip-slip-vulnerability. This vulnerability is low if the Karaf process user has limited permission on the filesystem. Any Apache Karaf releases prior 4.2.3 is impacted.

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*. It's 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" doesn't 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 it's possible to add a ACL to limit access. Users should update to Apache Karaf 4.2.9 or newer.

Apache Karaf Config service provides a install method (via service or MBean) that could be used to travel in any directory and overwrite existing file. The vulnerability is low if the Karaf process user has limited permission on the filesystem. Any Apache Karaf version before 4.2.5 is impacted. User should upgrade to Apache Karaf 4.2.5 or later.

Apache Karaf before 4.0.10 enables a shutdown port on the loopback interface, which allows local users to cause a denial of service (shutdown) by sending a shutdown command to all listening high ports.

Path traversal flaws