CVE-2026-100300
High
Description
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.
SeverityHigh
CVSS8.7
Exploit probability—
Product
ZooKeeper
PublishedNov 4, 2026
First seenNov 4, 2026
Weakness typeCWE-755CWE-755
How to fix
Update
- Apache ZooKeeper3.8.8 or 3.9.7 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Apache ZooKeeper | v ≤ 3.9.6 | 3.8.8 or 3.9.7 |
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