CVE-2024-4027: Undertow: outofmemoryerror in httpservletrequestimpl.getparameternames() can cause remote dos attacks

Published Jan 30, 2026
·
Updated

A flaw was found in Undertow. Servlets using a method that calls HttpServletRequestImpl.getParameterNames() can cause an OutOfMemoryError when the client sends a request with large parameter names. This issue can be exploited by an unauthorized user to cause a remote denial-of-service (DoS) attack.

Affected Software

2 affected componentsFixes available
Undertow Undertow
maven/io.undertow:undertow-core<2.3.21.Final
2.3.21.Final

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade maven/io.undertow:undertow-core to a version that resolves this vulnerability.

    Fixed in 2.3.21.Final

Event History

Jan 30, 2026
CVE Published
via MITRE·02:25 PM
Data Sourced
via MITRE·02:25 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·03:16 PM
DescriptionSeverityWeakness
Advisory Published
via GitHub·03:31 PM
Data Sourced
via GitHub·03:31 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2024-4027?

CVE-2024-4027 is classified as a medium severity vulnerability due to its potential for remote denial of service attacks.

2

How do I fix CVE-2024-4027?

To mitigate CVE-2024-4027, it's recommended to limit the length of HTTP parameter names in your application or update to the latest version of Undertow that addresses this issue.

3

What is the impact of CVE-2024-4027 on my application?

CVE-2024-4027 can lead to an OutOfMemoryError in applications that handle requests with excessively long parameter names, potentially crashing the server.

4

Which software is affected by CVE-2024-4027?

CVE-2024-4027 affects Undertow when servlets utilize the HttpServletRequestImpl.getParameterNames() method.

5

Can CVE-2024-4027 be exploited remotely?

Yes, CVE-2024-4027 can be exploited remotely through crafted HTTP requests with large parameter names.

Contact

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