CVE-2026-24281 (GCVE-0-2026-24281)

Vulnerability from cvelistv5 – Published: 2026-03-07 08:50 – Updated: 2026-03-10 17:37
VLAI?
Title
Apache ZooKeeper: Reverse-DNS fallback enables hostname verification bypass in ZooKeeper ZKTrustManager
Summary
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.
Severity ?
No CVSS data available.
CWE
  • CWE-350 - Reliance on Reverse DNS Resolution for a Security-Critical Action
  • CWE-295 - Improper Certificate Validation
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache ZooKeeper Affected: 3.9.0 , ≤ 3.9.4 (maven)
Affected: 3.8.0 , ≤ 3.8.5 (maven)
Create a notification for this product.
Credits
Nikita Markevich <markevich.nikita1@gmail.com>
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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