Advisory severityHigh7.5Apache Software Foundation

High [CVE-2026-79993] Apache ZooKeeper: 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 high-severity Apache Software Foundation advisory covers CVE-2026-79993 affecting Apache ZooKeeper.

Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.

CVE-2026-79993 Source published Sep 16, 2026Source updated Sep 18, 2026

VulniPulse record published Sep 16, 2026Record updated Sep 18, 2026

CVE-2026-79993

Affected products & platforms

Apache Software FoundationBig Data

Open source advisory

Android app · Google Play

Monitor future Apache Software Foundation CVEs from your phone.

Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.

Matching phone alertsOptional email delivery

Get CVE alerts See app features

Summary

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.

Affected versions

3.9.0 through 3.9.5
3.8.0 through 3.8.6.
through 3.8.6

Official advisory · high-confidence parse· fetched 20 days ago·verify at source

Fixed versions

3.9.6
3.8.7

Official advisory · high-confidence parse· fetched 20 days ago·verify at source

Mitigation checklist

Recommended fix / mitigation

Users are recommended to upgrade to version 3.9.6 or 3.8.7, which fixes the issue.

Official advisory · high-confidence parse· fetched 20 days ago·verify at source

Sources

Official and corroborating records used to build this advisory.

Official vendor advisoryofficial
Official advisory page fetched and parsed; accepted detail fields are attributed to this page.
Apache Software Foundation
CVE.org CNA recordCVE.org
Independent CNA record used for near-real-time discovery and missed-CVE reconciliation. Discovered from the machine-readable feed https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/delta.json; this link opens the CVE.org record for CVE-2026-79993 instead of the raw feed document.
CVE Program

Cross-references

Validate CVE metadata against the authoritative registries.

CVE-2026-79993NVD CVE.org MITRE

Official resources

ASF Security — reporting & CVE process
Official documentation
The Apache Software Foundation's official security page: how ASF CVEs are published and where each project's advisories live.
Apache project downloads (fixed releases)
Official documentation
Official ASF download tree — fetch the fixed release named in this advisory from the project's directory.

Discussion(0)

No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.