What is the CVSS score of CVE-2024-4027?

CVE-2024-4027 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.3%.

Which versions of Undertow. Servlets are affected by CVE-2024-4027?

CVE-2024-4027 affects Undertow-based applications and can be exploited to cause denial of service through memory exhaustion by sending requests with abnormally large parameter names.. A patch is available.

How to fix or mitigate CVE-2024-4027?

Within 24 hours: inventory all applications using Undertow and assess exposure; enable request size monitoring and alerting. Within 7 days: implement WAF rules to reject requests with excessively large parameter names and deploy network-level rate limiting; coordinate with development teams on remediation timeline. Within 30 days: apply vendor patch immediately upon release or pursue alternative mitigation strategies such as load balancer request filtering and Java heap tuning.

Undertow. Servlets CVE-2024-4027

HIGH

Improper Input Validation (CWE-20)

2026-01-30 secalert@redhat.com

GHSA-33hj-rcmx-86mv

Authentication Bypass

7.5

CVSS 3.1 · Vendor: redhat

Severity by source

Vendor (redhat) PRIMARY

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Red Hat

7.5 HIGH

qualitative

Primary rating from Vendor (redhat).

CVSS VectorVendor: redhat

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Patch released

Mar 31, 2026 - 21:13 nvd

Patch available

Analysis Generated

Mar 12, 2026 - 22:00 vuln.today

CVE Published

Jan 30, 2026 - 15:16 nvd

HIGH 7.5

Blast Radius

ecosystem impact

† from your stack dependencies † transitive graph · vuln.today resolves 4-path depth

13 maven packages depend on io.undertow:undertow-core (7 direct, 6 indirect)

Ecosystem-wide dependent count for version 2.4.0.Alpha1.

DescriptionCVE.org

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.

AnalysisAI

Technical ContextAI

Classified as CWE-20 (Improper Input Validation). 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.