---
id: CVE-2024-4027
title: A flaw was found in Undertow
summary: >-
  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 unaut…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-20
  - CWE-20
published: '2026-01-30'
updated: '2026-06-30'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2024-4027'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2024-4027'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2276410'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2024-4027'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2276410'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2024/cve-2024-4027.json
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
tags:
  - nvd
epss: 0.00355
epssPercentile: 0.29359
ingestedAt: '2026-07-03T18:53:52.136Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.