Is there a public exploit for CVE-2026-100300?

No public exploit for CVE-2026-100300 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-100300?

CVE-2026-100300 scores CVSS 8.7 (v4.0), rated high.

What does CVE-2026-100300 affect?

CVE-2026-100300 affects Apache Software Foundation Apache ZooKeeper.

8.7 High

Improper handling of exceptional conditions in the quota subsystem of Apache ZooKeeper allows an attacker able to write under the…

CVE-2026-100300

Improper handling of exceptional conditions in the quota subsystem of Apache ZooKeeper allows an attacker able to write under the /zookeeper/quota subtree — unauthenticated on default deployments, where that subtree is world-writable — to crash the server's critical request-processing thread and render the on-disk data directory permanently unbootable. This issue affects Apache ZooKeeper up to and including 3.9.6. Users are recommended to upgrade to version 3.8.8 or 3.9.7, which fixes the issue.

Assessment

CVSS: 8.7 (v4.0)
Severity: High
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 4 November 2026
Last updated: 4 November 2026
Affected: Apache Software Foundation · Apache ZooKeeper
Assigner: apache

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

https://lists.apache.org/thread.html/09pgg7rcpzz44noxgtvpzstwt8fmvsb0

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