Denial of Service (DoS) Affecting org.apache.zookeeper:zookeeper Open this link in a new tab package, versions [3.4.6, 3.4.10) [3.5.0-alpha, 3.5.3-beta)

  • Attack Complexity


  • Availability


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  • snyk-id


  • published

    21 May 2017

  • disclosed

    15 Feb 2017

  • credit


How to fix?

Upgrade org.apache.zookeeper:zookeeper to version 3.4.10, 3.5.3-beta or higher.


org.apache.zookeeper:zookeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services.

Affected versions of this package are vulnerable to Denial of Service (DoS). Four letter zookeeper commands (such as wchp/wchc ) are not properly handled, which leads to the server unable to serve legitimate client requests.


Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.

Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.

One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.

When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.

Two common types of DoS vulnerabilities:

  • High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.

  • Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm ws package