An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0. An attacker can upload arbitrary files through amavisd via a cpio loophole (extraction to /opt/zimbra/jetty/webapps/zimbra/public) that can lead to incorrect access to any other user accounts. Zimbra recommends pax over cpio. Also, pax is in the prerequisites of Zimbra on Ubuntu; however, pax is no longer part of a default Red Hat installation after RHEL 6 (or CentOS 6). Once pax is installed, amavisd automatically prefers it over cpio.
An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0. An attacker can upload arbitrary files through amavisd via a cpio loophole (extraction to /opt/zimbra/jetty/webapps/zimbra/public) that can lead to incorrect access to any other user accounts. Zimbra recommends pax over cpio. Also, pax is in the prerequisites of Zimbra on Ubuntu; however, pax is no longer part of a default Red Hat installation after RHEL 6 (or CentOS 6). Once pax is installed, amavisd automatically prefers it over cpio.