How severe is CVE-2024-4027?

CVE-2024-4027 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2024-4027 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2024-4027?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2024-4027 have an EU (EUVD) identifier?

Yes. CVE-2024-4027 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32593.

When was CVE-2024-4027 published?

CVE-2024-4027 was published on 2026-01-30 and last updated on 2026-06-30.

CVE-2024-4027

CVE-2024-4027 is a high-severity vulnerability with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-32593
Weakness: CWE-20
Published: 2026-01-30
Last modified: 2026-06-30

Description

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.

Frequently asked questions

What is CVE-2024-4027?: 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.
How severe is CVE-2024-4027?: CVE-2024-4027 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-4027 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2024-4027?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-4027 have an EU (EUVD) identifier?: Yes. CVE-2024-4027 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-32593.
When was CVE-2024-4027 published?: CVE-2024-4027 was published on 2026-01-30 and last updated on 2026-06-30.

References

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