# CVE-2021-37137: libnetty-java: The Snappy frame decoder function doesn't restrict the chunk length whichmay lead to excessive memory usage

CVE-2021-37137 is fixed in 2 products on 1 platform, first by RLSA-2022:8506, released November 16, 2022. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-37137
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0657
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 19, 2021

## Description

The Snappy frame decoder function doesn't restrict the chunk length whichmay lead to excessive memory usage. Beside this it also may buffer reservedskippable chunks until the whole chunk was received which may lead toexcessive memory usage as well. This vulnerability can be triggered bysupplying malicious input that decompresses to a very big size (via anetwork stream or a file) or by sending a huge skippable chunk.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libdb rocky 8 | 0:5.3.28-42.el8_4 | [RLSA-2022:8506](https://patchblox.com/security/data/fix/linux/rlsa-2022-8506.md) | Nov 16, 2022 |
| Linux | libnetty-java Ubuntu 18.04.6 LTS (bionic) | 1:4.1.7-4ubuntu0.1+esm2 | [libnetty-java 1:4.1.7-4ubuntu0.1+esm2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libnetty-java-1-4.1.7-4ubuntu0.1-esm2.md) | Dec 12, 2022 |
| Linux | libnetty-java Ubuntu 20.04 LTS (focal) | 1:4.1.45-1ubuntu0.1~esm1 | [libnetty-java 1:4.1.45-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libnetty-java-1-4.1.45-1ubuntu0.1-esm1.md) | Dec 12, 2022 |
| Linux | libnetty-java Ubuntu 22.04.1 LTS (jammy) | 1:4.1.48-4+deb11u1build0.22.04.1 | [libnetty-java 1:4.1.48-4+deb11u1build0.22.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-libnetty-java-1-4.1.48-4-deb11u1build0.22.04.1.md) | Dec 12, 2022 |
| Linux | libnetty-java Ubuntu 24.10 (oracular) | 4.1.48-6 | [libnetty-java 4.1.48-6](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-libnetty-java-4.1.48-6.md) | Jan 16, 2026 |
| Linux | libnetty-java Ubuntu 25.04 (plucky) | 4.1.48-6 | [libnetty-java 4.1.48-6](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-libnetty-java-4.1.48-6.md) | Jan 16, 2026 |

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Data as of 2026-11-08T19:12:23Z 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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