What is CVE-2026-44248?

CVE-2026-44248 is a medium-severity vulnerability in Io.netty Netty-codec-mqtt, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2026-05-13.

How severe is CVE-2026-44248?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Resource exhaustion in Io.netty Netty-codec-mqtt

CVE-2026-44248

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, the MQTT 5 header Properties section is parsed and buffered before any message size limit is applied. Specifically, in MqttDecod…

Vulnerability class: DoS (Denial of Service)

EPSS: 0.000 (4.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

Io.netty Netty-codec-mqtt — versions >= 4.2.0.Alpha1, < 4.2.13.Final, < 4.1.133.Final
Netty — versions >= 4.2.0.Alpha1, < 4.2.13.Final, < 4.1.133.Final

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)

Frequently asked questions

What is CVE-2026-44248?: CVE-2026-44248 is a medium-severity vulnerability in Io.netty Netty-codec-mqtt, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2026-05-13.
How severe is CVE-2026-44248?: Medium severity. CVSS v3 base score is 5.3 out of 10.