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CVE-2026-79993

HIGH 7.5 ALL-YEARS

Published 2026-09-16 · Last modified 2026-09-17 · apache · NVD: Analyzed

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.

ELEVATED IMPACT

Severe if exploited (CVSS 7.5), but no confirmed exploitation. Patch on a normal cadence.

Exploitation likelihood

0.6%chance of exploitation in 30 days · 48th percentile

○ In CISA KEV○ Public exploit / PoC◆ SSVC: exploitation none, automatable yes

Impact if exploited

7.5CVSS 3.1 · HIGH · ADP

  • ConfidentialityNone
  • IntegrityHigh
  • AvailabilityNone

What an attacker needs

  • ✓Access: Reachable over the network — no local access needed
  • ✓Privileges: No account or privileges required
  • ✓User interaction: No user interaction needed
  • ✓Complexity: No special conditions — reliably repeatable

✓ lowers the bar for an attacker · ⚠ raises it

Proof of concept & exploit code

No public exploit or proof-of-concept code is catalogued for this CVE (no ExploitDB, Nuclei, or CISA-KEV entry). It may still exist — search GitHub or check the references below.

Affected

Vendors Apache Software Foundation Apache

Products Apache Zookeeper Zookeeper

Weakness (CWE)

  • CWE-862: Missing Authorization

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Known Affected Software Configurations

VendorProductVersion range
ApacheZookeeper≥ 3.8.0 and < 3.8.7
ApacheZookeeper≥ 3.9.0 and < 3.9.6

All CVSS metrics

  • HIGH 7.5 v3.1 · ADP Primary
    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
  • HIGH 7.5 v3.1 · NVD Secondary
    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References

Advisories

Sources: NVD · CVE.org · EPSS