GHSA-jfg9-48mv-9qgx - Vulnerability details

5.3/10

CVSS 3.1

GHSA-jfg9-48mv-9qgx

resolved Published 2026-05-07 Updated 2026-05-14

GitHub Advisory

Show outdated versions

Vulnerability Data from Dependency-Track

Affected versions

5.6

5.6.1 5.6.0

5.5

5.5.17 5.5.16 5.5.15 5.5.14 5.5.13 5.5.12 5.5.11 5.5.10 5.5.9 5.5.8 5.5.7 5.5.6 5.5.5 5.5.4 5.5.3 5.5.2 5.5.1 5.5.0

5.4

5.4.11 5.4.10 5.4.9 5.4.8 5.4.7 5.4.6 5.4.5 5.4.4 5.4.3 5.4.2 5.4.1 5.4.0

Fixed in versions 5.7.0, 5.6.2, 5.5.18 and 5.4.12

Score

5.3 CVSS 3.1 GITHUB CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Description

### Impact 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`, Netty will repeatedly re-parse the enormous Properties sections and buffer the bytes in memory, until the entire thing parses to completion. This can cause high resource usage in both CPU and memory. ### Resources `ANT-2026-09608` https://docs.oasis-open.org/mqtt/mqtt/v5.0/os/mqtt-v5.0-os.html#_Toc3901027

Same vulnerability as

CVE-2026-44248 resolved according to EUVD-2026-30132

Analysis Read only

State

Justification

Recommandation

Workaround

The analysis can only be edited by the BlueMind security teams: log in.

CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation. CVE data may be incomplete, delayed, or inaccurate. This website and all information provided are offered on an “as is” basis without warranties of any kind. This site is not affiliated with, endorsed by, or sponsored by the CVE Program or The MITRE Corporation.

This site uses data from the National Vulnerability Database (NVD), obtained through Dependency-Track, but is not endorsed or certified by the NVD or the National Institute of Standards and Technology (NIST). NVD data may be incomplete, delayed, or inaccurate.

CVSS (Common Vulnerability Scoring System) is owned and managed by FIRST.Org, Inc. and used by permission. The links on CVSS vectors open the FIRST CVSS calculators (CVSS 3.0, 3.1 and 4.0), or the NVD calculator for CVSS 2.0. This site is not affiliated with, endorsed by, or sponsored by FIRST.

GitHub is a trademark of GitHub, Inc. GHSA identifiers and advisory data come from the GitHub Advisory Database, licensed under CC-BY 4.0. GHSA data may be incomplete, delayed, or inaccurate. This site is not affiliated with, endorsed by, or sponsored by GitHub, Inc.

Source of the EUVD data: European Vulnerability Database (EUVD), © European Union Agency for Cybersecurity (ENISA), reused with acknowledgement of the source as provided by the ENISA legal notice and IPR policy. Changes: CVEManager does not display the EUVD records as such; it uses their aliases to link the CVE and GHSA identifiers designating the same vulnerability. EUVD data may be incomplete, delayed, or inaccurate. This site is not affiliated with, endorsed by, or sponsored by ENISA or the European Union.