Description
Hostname verification in Apache ZooKeeper ZKTrustManager falls back to reverse DNS (PTR) when IP SAN validation fails, allowing attackers who control or spoof PTR records to impersonate ZooKeeper servers or clients with a valid certificate for the PTR name. It's important to note that attacker must present a certificate which is trusted by ZKTrustManager which makes the attack vector harder to exploit. Users are recommended to upgrade to version 3.8.6 or 3.9.5, which fixes this issue by introducing a new configuration option to disable reverse DNS lookup in client and quorum protocols.
Problem types
CWE-350 Reliance on Reverse DNS Resolution for a Security-Critical Action
CWE-295 Improper Certificate Validation
Product status
3.9.0 (maven)
3.8.0 (maven)
Credits
Nikita Markevich <markevich.nikita1@gmail.com>
References
lists.apache.org/thread/088ddsbrzhd5lxzbqf5n24yg0mwh9jt2