CVE-2026-79993
Received
Received - Intake
Authorization Bypass in Apache ZooKeeper
Vulnerability report for CVE-2026-79993, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-16
Last updated on: 2026-09-16
Assigner: Apache Software Foundation
Description
Description
The `deleteContainer` opcode (0x14/20) is processed without verifying the caller's ACL permissions, allowing any authenticated client to delete specific znodes in the data tree regardless of the ACL restrictions on the znode or its parent. This opcode is considered internal-only and the official client doesn't have API for it, but aΒ client that can open a plain TCP session on the ZooKeeper client port (2181 by default)Β - with NO authentication and NO ACL permissions - can delete anyΒ empty persistent znode (including regular persistent nodes, containerΒ nodes, and TTL nodes) by issuing the raw protocol OpCode deleteContainer (20).Β The deleteContainer request path completely skips both the session check andΒ the DELETE ACL check that are enforced by the regular delete (OpCode 2) path.Β This is an authorization bypass / ACL enforcement bug.
This issue affects Apache ZooKeeper: from 3.9.0 through 3.9.5, from 3.8.0 through 3.8.6.
Users are recommended to upgrade to version 3.9.6 or 3.8.7, which fixes the issue.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| apache | zookeeper | From 3.9.0 (inc) to 3.9.5 (inc) |
| apache | zookeeper | From 3.8.0 (inc) to 3.8.6 (inc) |
| apache | zookeeper | 3.9.6 |
| apache | zookeeper | 3.8.7 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-862 | The product does not perform an authorization check when an actor attempts to access a resource or perform an action. |