3.7
LOW CVSS 3.1
CVE-2026-44242
Micronaut Framework: Unbounded bundleCache in ResourceBundleMessageSource Allows Memory Exhaustion via Accept-Language Header
Description

Micronaut Framework is a JVM-based full stack Java framework designed for building modular, easily testable JVM applications. Prior to 4.10.22, the bundleCache is keyed by (Locale, baseName) where the locale originates from the HTTP Accept-Language header. In applications that explicitly register a ResourceBundleMessageSource bean and serve HTML error responses, an unauthenticated attacker can exhaust heap memory by sending requests with large numbers of unique Accept-Language values, each causing a new entry in the unbounded bundleCache. This vulnerability is fixed in 4.10.22.

INFO

Published Date :

May 12, 2026, 10:16 p.m.

Last Modified :

May 12, 2026, 10:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-44242 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 LOW [email protected]
Solution
Update Micronaut Framework to version 4.10.22 or later to fix heap exhaustion.
  • Update Micronaut Framework to version 4.10.22 or later.
  • Apply vendor patches or security updates as available.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-44242.

URL Resource
https://github.com/micronaut-projects/micronaut-core/security/advisories/GHSA-3rfq-4wpf-qqw3
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-44242 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-44242 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-44242 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-44242 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    May. 12, 2026

    Action Type Old Value New Value
    Added Description Micronaut Framework is a JVM-based full stack Java framework designed for building modular, easily testable JVM applications. Prior to 4.10.22, the bundleCache is keyed by (Locale, baseName) where the locale originates from the HTTP Accept-Language header. In applications that explicitly register a ResourceBundleMessageSource bean and serve HTML error responses, an unauthenticated attacker can exhaust heap memory by sending requests with large numbers of unique Accept-Language values, each causing a new entry in the unbounded bundleCache. This vulnerability is fixed in 4.10.22.
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
    Added CWE CWE-400
    Added Reference https://github.com/micronaut-projects/micronaut-core/security/advisories/GHSA-3rfq-4wpf-qqw3
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.