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Fencer Intel
high 7.5

CVE-2026-59739 json

Apache ZooKeeper: Information disclosure via SetWatches reconnect replay

published last mo. modified last mo. also BIT-zookeeper-2026-59739 , EUVD-2026-80330

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 46%
public exploits
0
none known

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.

Patch / fix

  • bitnami zookeeper 3.8.7, 3.9.6
  • apache zookeeper 3.8.7, 3.9.6
  • zookeeper Debian 14 3.9.6-1

debian advisories DEBIAN-CVE-2026-59739

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-59739 updated cvss 6.5

zookeeper: Apache ZooKeeper: Information disclosure via SetWatches reconnect replay

  • Red Hat AMQ Broker 7 parent, zookeeper, zookeeper-jute Red Hat build of Apache Camel 4 for Quarkus 3 flink-shaded-zookeeper-3 Red Hat build of Apache Camel for Spring Boot 4 flink-shaded-zookeeper-3, flink-shaded-zookeeper-parent Red Hat Fuse 7 zookeeper, zookeeper-jute, camel-zookeeper, camel-zookeeper-master, camel-zookeeper-starter, flink-shaded-zookeeper-3, +8 more Red Hat JBoss Enterprise Application Platform 8 parent, zookeeper Red Hat JBoss Enterprise Application Platform Expansion Pack parent, zookeeper
    +4 more products
    Red Hat Offline Knowledge Portal offline-knowledge-portal/rhokp-rhel9 Red Hat OpenShift AI (RHOAI) rhoai/odh-modelmesh-rhel9, rhoai/odh-spark-operator-rhel9, rhoai/odh-th-torch-cpu-py312-rhel9, rhoai/odh-th-torch-cuda-py312-rhel9, rhoai/odh-th06-cpu-torch210-py312-rhel9, rhoai/odh-th06-cpu-torch291-py312-rhel9, +3 more Red Hat OpenStack Platform 13 (Queens) puppet-zookeeper Red Hat OpenStack Platform 16.2 puppet-zookeeper
    affected: workaround, no fix available “Update to Apache ZooKeeper 3.8.7, 3.9.6, or later.”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
last mo.

Exploit prediction

0.55% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
OSV 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
bitnami zookeeper
>=3.8.0, <3.8.7
>=3.9.0, <3.9.6
3.8.7
3.9.6

Affected products

  • Apache Software Foundation Apache ZooKeeper

Classification

Weakness

References

Sources

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