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.
Metrics
Affected Vendors & Products
References
History
Mon, 09 Mar 2026 10:15:00 +0000
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Apache
Apache zookeeper |
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Apache
Apache zookeeper |
Sat, 07 Mar 2026 17:30:00 +0000
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Sat, 07 Mar 2026 09:00:00 +0000
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| 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. | |
| Title | Apache ZooKeeper: Reverse-DNS fallback enables hostname verification bypass in ZooKeeper ZKTrustManager | |
| Weaknesses | CWE-295 CWE-350 |
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| References |
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Status: PUBLISHED
Assigner: apache
Published: 2026-03-07T08:50:32.525Z
Updated: 2026-03-07T17:05:10.486Z
Reserved: 2026-01-21T19:40:25.776Z
Link: CVE-2026-24281
No data.
Status : Awaiting Analysis
Published: 2026-03-07T09:16:07.437
Modified: 2026-03-09T13:35:34.633
Link: CVE-2026-24281
No data.