# CVE-2024-1023: Io.vertx/vertx-core: memory leak due to the use of netty fastthreadlocal data structures in vertx

Status: published. Published: 2024-03-27. Updated: 2026-11-05.

A vulnerability in the Eclipse Vert.x toolkit results in a memory leak due to using Netty FastThreadLocal data structures. Specifically, when the Vert.x HTTP client establishes connections to different hosts, triggering the memory leak. The leak can be accelerated with intimate runtime knowledge, allowing an attacker to exploit this vulnerability. For instance, a server accepting arbitrary internet addresses could serve as an attack vector by connecting to these addresses, thereby accelerating the memory leak.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. (source: CNA: redhat)

## Affected products and versions

-  /  (vertx-core): 4.4.5 (affected); 4.4.6 (affected); 4.5.0 (affected); 4.5.1 (affected). Source: CNA: redhat
- Red Hat / CEQ 3.2 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Cryostat 2 on RHEL 8 (cryostat-tech-preview/cryostat-grafana-dashboard-rhel8): ≥ 2.4.0-7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cryostat 2 on RHEL 8 (cryostat-tech-preview/cryostat-operator-bundle): ≥ 2.4.0-4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cryostat 2 on RHEL 8 (cryostat-tech-preview/cryostat-reports-rhel8): ≥ 2.4.0-4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cryostat 2 on RHEL 8 (cryostat-tech-preview/cryostat-rhel8): ≥ 2.4.0-4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cryostat 2 on RHEL 8 (cryostat-tech-preview/cryostat-rhel8-operator): ≥ 2.4.0-9; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cryostat 2 on RHEL 8 (cryostat-tech-preview/jfr-datasource-rhel8): ≥ 2.4.0-4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / MTA-6.2-RHEL-9 (mta/mta-windup-addon-rhel9): ≥ 6.2.3-2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat AMQ Streams 2.7.0 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Apache Camel 4.4.1 for Spring Boot 3.2 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Quarkus 3.2.11.Final (io.vertx/vertx-core): ≥ 4.4.8.redhat-00001; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / RHINT Service Registry 2.5.11 GA (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / A-MQ Clients 2 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Migration Toolkit for Runtimes (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / OpenShift Serverless (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat AMQ Broker 7 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Apache Camel 4 for Quarkus 3 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Apache Camel for Spring Boot 3 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Build of Keycloak (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of OptaPlanner 8 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Quarkus (vertx-core): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Data Grid 8 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Fuse 7 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Integration Camel K 1 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Integration Camel Quarkus 2 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat JBoss Data Grid 7 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat JBoss Enterprise Application Platform 7 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat JBoss Enterprise Application Platform 8 (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat JBoss Enterprise Application Platform Expansion Pack (vert.x): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Process Automation 7 (vert.x): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 1.65% as of 2026-11-04; percentile 76.62%

- SSVC: exploitation poc; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-401

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2024:1662 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:1706 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:2088 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:2833 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3527 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:3989 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:4884 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2024-1023 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2260840 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://github.com/eclipse-vertx/vert.x/issues/5078 (CNA: redhat)

- https://github.com/eclipse-vertx/vert.x/pull/5080 (CNA: redhat)

- https://github.com/eclipse-vertx/vert.x/pull/5082 (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2024:1662 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:1706 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:2088 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:2833 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3527 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:3989 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:4884 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2024-1023 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2260840 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://github.com/eclipse-vertx/vert.x/issues/5078 (ADP: CVE; x_transferred)

- https://github.com/eclipse-vertx/vert.x/pull/5080 (ADP: CVE; x_transferred)

- https://github.com/eclipse-vertx/vert.x/pull/5082 (ADP: CVE; x_transferred)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2024-1023; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2024-1023; retrieved 2026-11-05; source updated Not reported

Revision: af28fe64ba2dce6156f8e25938cdcdd65f12c76df0b178dcc5e3e9666a423c03

Canonical: https://y2.dev/cve/CVE-2024-1023

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