PT-2026-24621 · Maven · Org.Apache.Zookeeper:Zookeeper

Published 2026-03-07 · Updated 2026-03-07

OSV

CVSS v3.1

7.4

High

Base vector

AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

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.

Fix

Improper Certificate Validation

Weakness Enumeration

CWE-297

CWE-295

Related Identifiers

GHSA-7XRH-HQFC-G7QR

Affected Products

Org.Apache.Zookeeper:Zookeeper

References · 7

• https://nvd.nist.gov/vuln/detail/CVE-2026-24281 · Security Note
• https://osv.dev/vulnerability/GHSA-7xrh-hqfc-g7qr · Vendor Advisory
• https://github.com/apache/zookeeper · Note
• https://github.com/apache/zookeeper/commit/66c4efecdda1302d9cfb3af9eedb122b74452bf3 · Note
• http://openwall.com/lists/oss-security/2026/03/07/4 · Note
• https://lists.apache.org/thread/088ddsbrzhd5lxzbqf5n24yg0mwh9jt2 · Note
• https://issues.apache.org/jira/browse/ZOOKEEPER-4986 · Note