---
title: "CVE-2021-37136\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2021-37136?format=md
keywords: index, follow
---

# CVE-2021-37136

Publication date 19 October 2021

Last updated 26 August 2025

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**7.5 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2021-37136?format=md#impact-score)

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## Description

The Bzip2 decompression decoder function doesn't allow setting size
restrictions on the decompressed output data (which affects the allocation
size used during decompression). All users of Bzip2Decoder are affected.
The malicious input can trigger an OOME and so a DoS attack

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| netty | 26.04 LTS resolute | Fixed 4.1.48-6 |
| 25.10 questing | Fixed 4.1.48-6 |
| 25.04 plucky | Fixed 4.1.48-6 |
| 24.10 oracular | Fixed 4.1.48-6 |
| 24.04 LTS noble | Fixed 4.1.48-6 |
| 23.10 mantic | Ignored end of life, was needs-triage |
| 23.04 lunar | Ignored end of life, was needs-triage |
| 22.10 kinetic | Fixed 1:4.1.48-5ubuntu0.1 |
| 22.04 LTS jammy | Fixed 1:4.1.48-4+deb11u1build0.22.04.1 |
| 21.10 impish | Ignored end of life |
| 21.04 hirsute | Ignored end of life |
| 20.04 LTS focal | Fixed 1:4.1.45-1ubuntu0.1~esm1  Ubuntu Pro |
| 18.04 LTS bionic | Fixed 1:4.1.7-4ubuntu0.1+esm2  Ubuntu Pro |
| 16.04 LTS xenial | Fixed 1:4.0.34-1ubuntu0.1~esm1  Ubuntu Pro |
| 14.04 LTS trusty | Needs evaluation |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

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## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | None |
  | Integrity impact | None |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.5 · High |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37136)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2021-37136)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2021-37136)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2021-37136)

### Related Ubuntu Security Notices (USN)

+ [USN-6049-1](https://usn.ubuntu.com/USN-6049-1)
+ Netty vulnerabilities
+ 28 April 2023

### Other references

* <https://github.com/netty/netty/security/advisories/GHSA-grg4-wf29-r9vv>
* <https://www.cve.org/CVERecord?id=CVE-2021-37136>