Apache ZooKeeper vulnerable to information disclosure in persistent watchers handlingGHSA-r978-9m6m-6gm6
MEDIUMFix: apache/zookeeper@29c7b94GHSA-r978-9m6m-6gm6 is a medium-severity (CVSS 5.3) CWE-862 vulnerability in org.apache.zookeeper:zookeeper. A fix is available for org.apache.zookeeper:zookeeper — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-r978-9m6m-6gm6.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
org.apache.zookeeper:zookeeper☕org.apache.zookeeper:zookeeper☕org.apache.zookeeper:zookeeperReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Information disclosure in persistent watchers handling in Apache ZooKeeper due to missing ACL check. It allows an attacker to monitor child znodes by attaching a persistent watcher (addWatch command) to a parent which the attacker has already access to. ZooKeeper server doesn't do ACL check when the persistent watcher is triggered and as a consequence, the full path of znodes that a watch event gets triggered upon is exposed to the owner of the watcher. 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 3.9.2, 3.8.4 which fixes the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.zookeeper:zookeeper | ≥ 3.8.0&&< 3.8.4 | 3.8.4org.apache.zookeeper:zookeeper:3.8.4 |
| ☕Maven | org.apache.zookeeper:zookeeper | ≥ 3.9.0&&< 3.9.2 | 3.9.2org.apache.zookeeper:zookeeper:3.9.2 |
| ☕Maven | org.apache.zookeeper:zookeeper | ≥ 3.6.0 | No fix |
Affected Products
zookeeperapacheDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.zookeeper:zookeeper, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.zookeeper:zookeeper to 3.8.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r978-9m6m-6gm6 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Only the path is exposed by this vulnerability, not the data in the znode. Since the znode path may contain sensitive information such as usernames or login IDs, the impact on confidentiality is "High".
Frequently Asked Questions
Is GHSA-r978-9m6m-6gm6 in your dependencies?
Find it across Maven, including transitive dependencies.