CVE-2026-79993
Fixed in a distro release EPSS <1%CVSS 7.5
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 a client that can open a plain TCP session on the ZooKeeper client port (2181 by default) - with NO authentication and NO ACL permissions - can delete any empty persistent znode (including regular persistent nodes, container nodes, and TTL nodes) by issuing the raw protocol OpCode deleteContainer (20). The deleteContainer request path completely skips both the session check and the DELETE ACL check that are enforced by the regular delete (OpCode 2) path. 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.
Products: Apache Software Foundation Apache ZooKeeper
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Debian 12 | zookeeper | no fix |
| Debian 13 | zookeeper | no fix |
| Debian 14 | zookeeper | 3.9.6-1 |
| Ubuntu 20.04 LTS | zookeeper | no fix |
| Ubuntu 22.04 LTS | zookeeper | no fix |
| Ubuntu 24.04 LTS | zookeeper | no fix |
| Ubuntu 26.04 LTS | zookeeper | no fix |
| Ubuntu 26.10 | zookeeper | no fix |
| Ubuntu Pro 14.04 LTS | zookeeper | no fix |
| Ubuntu Pro 16.04 LTS | zookeeper | no fix |
| Ubuntu Pro 18.04 LTS | zookeeper | no fix |