Go to homepageCyberStrike

Menu

Star on GitHub · 3.4k
Sign inDownload

CVE-2026-59739

7.5 · HIGH

Information disclosure via SetWatches reconnect replay in Apache ZooKeeper due to missing ACL check.

Published Sep 16, 2026apacheCWE-862EPSS 0.55%

Overview

CVE-2026-59739 is a high-severity vulnerability affecting apache zookeeper. It was published on September 16, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).

This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.

Technical description

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.

Remediation

Check the references section for vendor advisories and patches from apache. Update zookeeper to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected products

VendorProductVersionsStatus
apachezookeeper>= 3.8.0, < 3.8.7Affected

References

Reflists.apache.org/thread/v0lrwsbdxvx6w67p3z7fxf3hzyncq55l

How CyberStrike helps

Frequently asked questions

What is CVE-2026-59739?

CVE-2026-59739 is a high-severity vulnerability affecting apache zookeeper. It was published on September 16, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-59739?

This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.

How do I fix or remediate CVE-2026-59739?

Check the references section for vendor advisories and patches from apache. Update zookeeper to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

How can CyberStrike help with CVE-2026-59739?

CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2026-59739 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.

Related HIGH CVEs from 2026

View all
Browse by year2026202520242023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999
LiveWatch live →