Denial of Service (DoS) Affecting org.apache.tomcat.embed:tomcat-embed-core package, versions [8.5.0,8.5.56)[9.0.0.M1,9.0.36)[10.0.0-M1,10.0.0-M6)


Severity

Recommended
0.0
high
0
10

CVSS assessment made by Snyk's Security Team. Learn more

Threat Intelligence

Exploit Maturity
Proof of concept
EPSS
0.18% (57th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications

Snyk Learn

Learn about Denial of Service (DoS) vulnerabilities in an interactive lesson.

Start learning
  • Snyk IDSNYK-JAVA-ORGAPACHETOMCATEMBED-1728268
  • published28 Jun 2020
  • disclosed28 Jun 2020
  • creditUnknown

Introduced: 28 Jun 2020

CVE-2020-11996  (opens in a new tab)
CWE-400  (opens in a new tab)

How to fix?

Upgrade org.apache.tomcat.embed:tomcat-embed-core to version 8.5.56, 9.0.36, 10.0.0-M6 or higher.

Overview

org.apache.tomcat.embed:tomcat-embed-core is a Core Tomcat implementation.

Affected versions of this package are vulnerable to Denial of Service (DoS). A specially crafted sequence of HTTP/2 requests could trigger high CPU usage for several seconds. If a sufficient number of such requests were made on concurrent HTTP/2 connections, the server could become unresponsive.

Details

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

CVSS Scores

version 3.1