# CVE-2025-55163: libnetty-java: Netty is an asynchronous, event-driven network application framework

CVE-2025-55163 is fixed in 3 products on 1 platform, first by DEBIAN-CVE-2025-55163, released August 13, 2025. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2025-55163
- Priority: High
- CVSS: 7.5 (Medium)
- EPSS: 0.0113
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 13, 2025

## Description

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.124.Final and 4.2.4.Final, Netty is vulnerable to MadeYouReset DDoS. This is a logical vulnerability in the HTTP/2 protocol, that uses malformed HTTP/2 control frames in order to break the max concurrent streams limit - which results in resource exhaustion and distributed denial of service. This issue has been patched in versions 4.1.124.Final and 4.2.4.Final.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libnetty-java Ubuntu 18.04.6 LTS (bionic) | 1:4.1.7-4ubuntu0.1+esm7 | [libnetty-java 1:4.1.7-4ubuntu0.1+esm7](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libnetty-java-1-4.1.7-4ubuntu0.1-esm7.md) | Dec 15, 2025 |
| Linux | libnetty-java Ubuntu 20.04 LTS (focal) | 1:4.1.45-1ubuntu0.1~esm7 | [libnetty-java 1:4.1.45-1ubuntu0.1~esm7](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libnetty-java-1-4.1.45-1ubuntu0.1-esm7.md) | Dec 15, 2025 |
| Linux | libnetty-java Ubuntu 22.04.1 LTS (jammy) | 1:4.1.48-4+deb11u2ubuntu0.2+esm1 | [libnetty-java 1:4.1.48-4+deb11u2ubuntu0.2+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-libnetty-java-1-4.1.48-4-deb11u2ubuntu0.2-esm1.md) | Dec 15, 2025 |
| Linux | libnetty-java Ubuntu 24.04.5 LTS (noble) | 1:4.1.48-9ubuntu0.2+esm1 | [libnetty-java 1:4.1.48-9ubuntu0.2+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libnetty-java-1-4.1.48-9ubuntu0.2-esm1.md) | Dec 15, 2025 |
| Linux | netty Debian 12.15 (bookworm) | 1:4.1.48-7+deb12u2 | [DSA-6160-1](https://patchblox.com/security/data/fix/linux/dsa-6160-1.md) | Mar 11, 2026 |
| Linux | netty Debian 13.5 (trixie) | 1:4.1.48-10+deb13u1 | [DSA-6160-1](https://patchblox.com/security/data/fix/linux/dsa-6160-1.md) | Mar 11, 2026 |
| Linux | netty Debian 14 | 1:4.1.48-11 | [DEBIAN-CVE-2025-55163](https://patchblox.com/security/data/fix/linux/debian-cve-2025-55163.md) | Aug 13, 2025 |
| Linux | netty opensuse-leap 15.6 | 4.1.126-150200.4.34.1 | [SUSE-SU-2025:03114-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03114-1.md) | Sep 9, 2025 |
| Linux | netty sles 15.6 | 4.1.126-150200.4.34.1 | [SUSE-SU-2025:03114-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03114-1.md) | Sep 9, 2025 |
| Linux | netty sles 15.7 | 4.1.126-150200.4.34.1 | [SUSE-SU-2025:03114-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03114-1.md) | Sep 9, 2025 |
| Linux | netty-tcnative opensuse-leap 15.6 | 2.0.73-150200.3.30.1 | [SUSE-SU-2025:03114-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03114-1.md) | Sep 9, 2025 |
| Linux | netty-tcnative sles 15.6 | 2.0.73-150200.3.30.1 | [SUSE-SU-2025:03114-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03114-1.md) | Sep 9, 2025 |
| Linux | netty-tcnative sles 15.7 | 2.0.73-150200.3.30.1 | [SUSE-SU-2025:03114-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03114-1.md) | Sep 9, 2025 |

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Data as of 2026-11-09T07:25:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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