CVE-2024-1300 is a medium-severity (CVSS 5.4) CWE-772 vulnerability in io.vertx:vertx-core. A fix is available for io.vertx:vertx-core — see the affected versions and patch details below.
Eclipse Vert.x vulnerable to a memory leak in TCP servers
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-1300.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
io.vertx:vertx-core☕io.vertx:vertx-coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
A vulnerability in the Eclipse Vert.x toolkit causes a memory leak in TCP servers configured with TLS and SNI support. When processing an unknown SNI server name assigned the default certificate instead of a mapped certificate, the SSL context is erroneously cached in the server name map, leading to memory exhaustion. This flaw allows attackers to send TLS client hello messages with fake server names, triggering a JVM out-of-memory error.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.vertx:vertx-core | ≥ 4.3.4&&< 4.4.8 | 4.4.8io.vertx:vertx-core:4.4.8 |
| ☕Maven | io.vertx:vertx-core | ≥ 4.5.0&&< 4.5.3 | 4.5.3io.vertx:vertx-core:4.5.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.vertx:vertx-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update io.vertx:vertx-core to 4.4.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-1300 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This affects only TLS servers with SNI enabled.
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: Red Hat security advisory for CVE-2024-1300 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| CEQ 3.2 | vertx-core | RHSA-2024:1706 |
| Cryostat 2 on RHEL 8 | cryostat-tech-preview/cryostat-grafana-dashboard-rhel8:2.4.0-7 | RHSA-2024:2088 |
| Migration Toolkit for Runtimes 1 on RHEL 8 | mtr/mtr-operator-bundle:1.2-18 | RHSA-2024:1923 |
| MTA-6.2-RHEL-9 | mta/mta-windup-addon-rhel9:6.2.3-2 | RHSA-2024:3989 |
| Red Hat AMQ Streams 2.7.0 | vertx-core | RHSA-2024:3527 |
| Red Hat build of Apache Camel 4.4.1 for Spring Boot 3.2 | vertx-core | RHSA-2024:4884 |
| Red Hat build of Quarkus 3.2.11.Final | io.vertx/vertx-core:4.4.8.redhat-00001 | RHSA-2024:1662 |
| RHINT Service Registry 2.5.11 GA | vertx-core | RHSA-2024:2833 |
Frequently Asked Questions
Is CVE-2024-1300 in your dependencies?
Find it across Maven, including transitive dependencies.