CVE-2026-79993
No exploitation reported by the sources we read.
- Published2026-09-16
- Fixed in3.9.6 · 3.8.7
- WeaknessCWE-862
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
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.
Timeline
dates in UTC- 2026-09-1610:16CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-79993?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-79993?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD · OSV| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 3.9 | ≥ 3.9.0, < 3.9.6 | 3.9.6 | NVD · OSV |
| 3.8 | ≥ 3.8.0, < 3.8.7 | 3.8.7 | NVD · OSV |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Vendor advisories
zookeeper: Apache ZooKeeper: Unauthorized znode deletion via missing ACL check
zookeeper as a component of Red Hat AMQ Broker 7 · zookeeper as a component of Red Hat build of Apache Camel for Spring Boot 4 · zookeeper as a component of Red Hat build of Debezium 3 · +6 more
Red Hat Security Advisory: Red Hat build of Debezium 3.6.3 release
Fix
- Update Apache zookeeper to 3.9.6 · 3.8.7
- Vendor fix Red Hat Product Security RHSA-2026:83612 · 1 productBefore applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
- Workaround from the vendor Red Hat Product Security RHSA-2026:83612 · 1 productMitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
- No fix available, says the vendor Red Hat Product Security CVE-2026-79993 · 6 productsAffected
- No fix planned, says the vendor Red Hat Product Security CVE-2026-79993 · 3 productsWill not fix
Advisories and patches
- lists.apache.orgVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Published
- 2026-09-16
- Last Modified
- 2026-09-18
- NVD status
- Analyzed
Frequently asked questions
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.