{"id":"CVE-2026-100300","title":"Apache ZooKeeper: Unauthenticated persistent denial of service via unvalidated quota-node data and paths crashing the transaction-apply thread","summary":"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 — t…","severity":"high","cvss":8.7,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","cvssSource":"cna","cwe":["CWE-755"],"vendor":"Apache Software Foundation","product":"org.apache.zookeeper:zookeeper","affected":["org.apache.zookeeper:zookeeper >= 3.9.0 <= 3.9.6","org.apache.zookeeper:zookeeper >= 3.8.0 <= 3.8.7"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-11-04T14:35:55.242898Z"},"published":"2026-11-04","updated":"2026-11-04","sourceUpdated":"2026-11-04T15:18:55.306Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-100300","references":[{"url":"https://lists.apache.org/thread.html/09pgg7rcpzz44noxgtvpzstwt8fmvsb0"}],"tags":["cve.org"],"ingestedAt":"2026-11-05T21:36:00.430Z","slug":"CVE-2026-100300","body":"## Overview\n\nImproper 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.\n\nThis 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.\n\n## Affected\n\n- `org.apache.zookeeper:zookeeper >= 3.9.0 <= 3.9.6`\n- `org.apache.zookeeper:zookeeper >= 3.8.0 <= 3.8.7`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":47.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}