CVE-2026-115448
Received
Received - Intake
Denial of Service in Apache ZooKeeper via Uncontrolled Recursion
Vulnerability report for CVE-2026-115448, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-04
Last updated on: 2026-11-04
Assigner: Apache Software Foundation
Description
Description
Uncontrolled recursion in Apache ZooKeeper. The server serializes its data tree to a snapshot by recursing one stack frame per znode level, with no depth bound. A client permitted to create znodes (the default root ACL is open) can build a chain of nested znodes deep enough that taking a snapshot exhausts the JVM stack and kills the snapshot thread; sizes stay within jute.maxbuffer, so existing limits do not prevent it. This is a denial of service that becomes persistent: on restart the server rebuilds the deep tree from its transaction log and fails again while taking the startup snapshot, so it does not return to service, and recovery can entail data loss. The same log affects a leader and its followers, so it can spread across an ensemble.
This issue affects Apache ZooKeeper 3.8.0 through 3.8.7 and 3.9.0 through 3.9.6. Users are recommended to upgrade to 3.8.8 or 3.9.7, which fix the issue. As a workaround, use ACLs and authentication to restrict znode creation rather than relying on the default open root ACL.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| Apache Software Foundation | Apache ZooKeeper | 3.9.0 |
| Apache Software Foundation | Apache ZooKeeper | 3.8.0 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-770 | The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated. |
