Review reviewHigh

CVE-2026-44248

netty netty, netty-codec-mqtt, Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16

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 MqttDecoder, the decodeVariableHeader() method is called before the bytesRemainingBeforeVariableHeader > maxBytesInMessage check. The decodeVariableHeader() can call other methods which will call decodeProperties(). Effectively, Netty does not apply any limits to the size of the properties being decoded. Additionally, because MqttDecoder extends ReplayingDecoder, N...

CVSS: 7.5
EPSS: 0.49%
CISA KEV: Not listed
Published: 2026.05.14

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.49%

Technical severityCVSS 7.5

Vulnerability overview

Affected product and versions

Product: netty netty, netty-codec-mqtt, Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16
Affected versions: >= >= 4.2.0.Alpha1, < 4.2.13.Final, >= < 4.1.133.Final, < 4.1.133, >= 4.2.0 < 4.2.13
Fixed versions: 4.1.133, 4.2.13

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that netty netty, netty-codec-mqtt, Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16 and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: CWE-400, CWE-770