Vulnerability 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 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Apache | Zookeeper | >= 3.8.0, < 3.8.7 |
Related Weaknesses (CWE)
References
- https://lists.apache.org/thread/9cw3rmrzhqpct26v8j18fy41bghlq8y5Mailing ListVendor Advisory
- http://www.openwall.com/lists/oss-security/2026/09/15/5Mailing List
FAQ
What is CVE-2026-79993?
CVE-2026-79993 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 r...
How severe is CVE-2026-79993?
CVE-2026-79993 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-79993?
Check the references section above for vendor advisories and patch information. Affected products include: Apache Zookeeper.