---
title: CVE-2021-20193
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-2021-20193
---

# CVE-2021-20193

Publication date 26 March 2021

Last updated 25 August 2025

---

Ubuntu priority

**Low**

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

## Cvss 3 Severity Score

**3.3 · Low**

[Score breakdown](https://ubuntu.com/security/CVE-2021-20193#impact-score)

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## Description

A flaw was found in the src/list.c of tar 1.33 and earlier. This flaw
allows an attacker who can submit a crafted input file to tar to cause
uncontrolled consumption of memory. The highest threat from this
vulnerability is to system availability.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2021-20193#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| tar | 23.04 lunar | Fixed 1.34+dfsg-1build1 |
| 22.10 kinetic | Fixed 1.34+dfsg-1build1 |
| 22.04 LTS jammy | Fixed 1.34+dfsg-1build1 |
| 21.10 impish | Fixed 1.34+dfsg-1build1 |
| 21.04 hirsute | Fixed 1.34+dfsg-1build1 |
| 20.10 groovy | Ignored end of life |
| 20.04 LTS focal | Fixed 1.30+dfsg-7ubuntu0.20.04.2 |
| 18.04 LTS bionic | Fixed 1.29b-2ubuntu0.3 |
| 16.04 LTS xenial | Fixed 1.28-2.1ubuntu0.2+esm1  Ubuntu Pro |
| 14.04 LTS trusty | Fixed 1.27.1-1ubuntu0.1+esm2  Ubuntu Pro |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2021-20193#patch-details)

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## Notes

---

### [sbeattie](https://launchpad.net/~sbeattie)

the tar command failed to free memory. As this is a command
line tool denial of service, this has been rated as priority low

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| tar | * Upstream:   [?id=d9d](https://git.savannah.gnu.org/cgit/tar.git/commit/?id=d9d4435692150fa8ff68e1b1a473d187cc3fd777) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

3.3 · Low

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 3.3 · Low |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-20193)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2021-20193)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2021-20193)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2021-20193)

### Related Ubuntu Security Notices (USN)

+ [USN-5329-1](https://usn.ubuntu.com/USN-5329-1)
+ tar vulnerability
+ 15 March 2022

### Other references

* <https://savannah.gnu.org/bugs/?59897>
* <https://www.cve.org/CVERecord?id=CVE-2021-20193>