Vulnerability DatabaseCVE-2022-37393

CVE-2022-37393:
Zimbra Collaboration Server vulnerability analysis and mitigation

Overview

CVE-2022-37393 is a privilege escalation vulnerability in Zimbra Collaboration Suite, discovered in October 2021 and publicly disclosed on August 16, 2022. The vulnerability allows a user with a zimbra user account to escalate privileges to root by exploiting Zimbra's sudo configuration that permits the zimbra user to execute the zmslapd binary as root with arbitrary parameters (AttackerKB, Rapid7 Blog).

Technical details

The vulnerability stems from Zimbra's sudo configuration that allows the zimbra user to execute the zmslapd binary with root privileges and arbitrary parameters. As part of its functionality, zmslapd can load user-defined configuration files that include plugins in the form of .so files, which also execute as root. The vulnerability has a CVSS v3 Base Score of 7.8 (High) with vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H, indicating local access requirement with low attack complexity (AttackerKB).

Impact

If successfully exploited, the vulnerability allows an attacker with zimbra user access to escalate to root privileges, potentially gaining complete control over the Zimbra server. This is particularly concerning as Zimbra servers often contain sensitive email data and can be used as a stepping stone for further network compromise (AttackerKB).

Mitigation and workarounds

Organizations using Zimbra should update to the latest available version. Additionally, it is recommended to block internet traffic to Zimbra servers where possible and configure Zimbra to block external Memcached, even on patched versions (Rapid7 Blog).