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CVE-2026-59739 (GCVE-0-2026-59739)

Vulnerability from cvelistv5 – Published: 2026-09-16 09:26 – Updated: 2026-09-16 09:26
VLAI
Title
Apache ZooKeeper: Information disclosure via SetWatches reconnect replay
Summary
Information disclosure via SetWatches reconnect replay in Apache ZooKeeper due to missing ACL check. An attacker can discover ACL-restricted paths by registering exists-watches on non-existent paths, then reconnecting after the paths are created with restricted ACLs. Issue is caused by incomplete fix for CVE-2024-23944 (ZOOKEEPER-4799). The fix added ACL checking to WatchManager.triggerWatch(). However, DataTree.setWatches() — the SetWatches/SetWatches2 reconnect replay handler — still calls watcher.process(event) with null ACL, bypassing the check entirely. It's important to note that only the path is exposed by this vulnerability, not the data of znode, but since znode path can contain sensitive information like user name or login ID, this issue is potentially critical. Users are recommended to upgrade to version 3.9.6, 3.8.7 which fixes the issue.
Severity
No CVSS data available.
CWE
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache ZooKeeper Affected: 3.9.0 , ≤ 3.9.5 (maven)
Affected: 3.8.0 , ≤ 3.8.6 (semver)
guessed Create a notification for this product.
Show details on NVD website

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