CVE-2022-41352
Description
An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0. An attacker can upload arbitrary files through amavis 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, amavis automatically prefers it over cpio.
Summary dbcve.org
Zimbra Collaboration Suite 8.8.15 and 9.0 ship with amavis, which can use cpio for archive handling. An attacker can craft a message that triggers cpio to extract arbitrary files into the web-accessible directory /opt/zimbra/jetty/webapps/zimbra/public, enabling unauthorized access to other user accounts (e.g., via planted JSP/servlets or session-stealing resources). Installing pax causes amavis to automatically prefer pax over cpio, closing the loophole.
Mitigation
Install the pax package on every Zimbra host (RHEL/CentOS 7+ systems lack it by default) and restart amavis so it prefers pax over cpio; additionally, upgrade to a ZCS release where the issue is addressed upstream and audit /opt/zimbra/jetty/webapps/zimbra/public for any attacker-planted files.