Two four letter word commands "wchp/wchc" are CPU intensive and could cause spike of CPU utilization on Apache ZooKeeper server if abused, w

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• apache zookeeper3.4.0
• apache zookeeper3.4.1
• apache zookeeper3.4.2
• apache zookeeper3.4.3
• apache zookeeper3.4.4
• apache zookeeper3.4.5
• apache zookeeper3.4.6
• apache zookeeper3.4.7
• apache zookeeper3.4.8
• apache zookeeper3.4.9
• apache zookeeper3.5.0
• apache zookeeper3.5.1
• apache zookeeper3.5.2
• debian debian linux8.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.

• Apache Software Foundation Apache ZooKeeper

  • 3.4.0 to 3.4.9, 3.5.0 to 3.5.2affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Other highest-scoring records for the same primary product.

• CVE-2023-44981Apache ZooKeeper: Authorization bypass in SASL Quorum Peer Authentication
  37Monitor
• CVE-2024-51504Apache ZooKeeper: Authentication bypass with IP-based authentication in Admin Server
  36Monitor
• CVE-2016-5017Buffer overflow in the C cli shell in Apache Zookeeper before 3.4.9 and 3.5.x before 3.5.3, when using the "cmd:" batch mode syntax, allows
  34Monitor
• CVE-2018-8012No authentication/authorization is enforced when a server attempts to join a quorum in Apache ZooKeeper before 3.4.10, and 3.5.0-alpha throu
  33Monitor
• CVE-2026-79993Apache ZooKeeper: Missing ACL check on deleteContainer opcode allows unauthorized deletion of any empty persistent/container znode
  30Monitor
• CVE-2026-59969Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode
  30Monitor

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Root cause

A function added for development or support ships to production without authentication. It often relies on the assumption that it is “only reachable from the internal network.”

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1// Added for the support team2app.post("/maintenance/reset", resetDevice);

1if (config.maintenanceEnabled) {2  app.post(3    "/maintenance/reset",4    requireSession, requireRole("admin"), resetDevice5  );6}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.