CVE-2021-33609: Vaadin server Denial of Service Vulnerability

MODERATE
Advisory Identifier: GHSA-qcgx-crrx-38v5
Share
CVSS 4.3
CWE-400 CWE-20
Published
Advisory Summary

CVE-2021-33609 is a MODERATE (CVSS 4.3) denial of service vulnerability (CWE-400: Uncontrolled Resource Consumption) affecting Vaadin server libraries in the Maven ecosystem. The issue involves denial of service in datacommunicator class in vaadin 8. Remediation is available by upgrading affected packages to version 8.14.1.

CVE-2021-33609 at a Glance

CVE Identifier CVE-2021-33609
GHSA Identifier GHSA-qcgx-crrx-38v5
Severity MODERATE
CVSS v3.1 Base Score 4.3
CWE Classification CWE-400: Uncontrolled Resource Consumption
Affected Product Vaadin server
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 4.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability Low (A:L)

How to Fix CVE-2021-33609

To remediate this vulnerability, upgrade all affected Vaadin server dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

com.vaadin:vaadin-server fixed: 8.14.1 
<dependency>
    <groupId>com.vaadin</groupId>
    <artifactId>vaadin-server</artifactId>
    <version>8.14.1</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=com.vaadin

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2021-33609, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=com.vaadin

Analyze the terminal output to locate any version of Vaadin server in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 8.14.1), your application is affected.

Note: The mvn dependency:tree -Dincludes=com.vaadin command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-400: Uncontrolled Resource Consumption, where the product does not properly control the allocation and maintenance of a limited resource. In Vaadin server, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Missing check in `DataCommunicator` class in `com.vaadin:vaadin-server` versions 8.0.0 through 8.14.0 (Vaadin 8.0.0 through 8.14.0) allows authenticated network attacker to cause heap exhaustion by requesting too many rows of data.

CVE-2021-33609 Affected Vaadin server Versions

1 component(s)
Fixed Versions:
8.14.1
Product / Package Ecosystem Affected Versions Fixed Version
com.vaadin:vaadin-server
maven/com.vaadin/vaadin-server
Maven
≥ 8.0.6
< 8.14.1
8.14.1

References

GitHub Advisory / Wiki ADVISORY
https://github.com/vaadin/framework/security/advisories/GHSA-qcgx-crrx-38v5
NVD — CVE-2021-33609 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-33609
Vaadin server Source Repository REPOSITORY
https://github.com/vaadin/framework/pull/12415
Vaadin server Source Repository REPOSITORY
https://github.com/vaadin/framework
Vaadin server Security Information SECURITY
https://vaadin.com/security/cve-2021-33609

Frequently Asked Questions

What is CVE-2021-33609?
CVE-2021-33609 is a security vulnerability in Vaadin server involving Denial of service in DataCommunicator class in Vaadin 8 under CWE-400: Uncontrolled Resource Consumption.
Which Vaadin server versions are affected?
Affected versions include releases prior to 8.14.1 across affected packages: com.vaadin:vaadin-server.
What version fixes CVE-2021-33609?
Upgrading to 8.14.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is vaadin-server affected?
Yes, com.vaadin:vaadin-server is affected in releases prior to 8.14.1. Upgrade your dependency to 8.14.1 or later.
What is the CVSS score of CVE-2021-33609?
CVE-2021-33609 has a CVSS v3.1 base score of 4.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.
What CWE is associated with CVE-2021-33609?
CVE-2021-33609 is classified under CWE-400: Uncontrolled Resource Consumption (The product does not properly control the allocation and maintenance of a limited resource.).
How can I check Maven dependencies for CVE-2021-33609?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=com.vaadin'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-qcgx-crrx-38v5",
  "modified" : "2024-05-15T05:13:04Z",
  "published" : "2021-10-13T18:54:09Z",
  "aliases" : [ "CVE-2021-33609" ],
  "summary" : "Denial of service in DataCommunicator class in Vaadin 8",
  "details" : "Missing check in `DataCommunicator` class in `com.vaadin:vaadin-server` versions 8.0.0 through 8.14.0 (Vaadin 8.0.0 through 8.14.0) allows authenticated network attacker to cause heap exhaustion by requesting too many rows of data.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.vaadin:vaadin-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "8.0.6"
      }, {
        "fixed" : "8.14.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/vaadin/framework/security/advisories/GHSA-qcgx-crrx-38v5"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-33609"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/vaadin/framework/pull/12415"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/vaadin/framework"
  }, {
    "type" : "WEB",
    "url" : "https://vaadin.com/security/cve-2021-33609"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20", "CWE-400" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-10-13T17:39:24Z",
    "nvd_published_at" : "2021-10-13T11:15:00Z"
  }
}