---
id: CVE-2021-20193
title: A flaw was found in the src/list.c of tar 1.33 and earlier
summary: >-
  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
  avai…
severity: low
cvss: 3.3
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L'
cwe:
  - CWE-401
  - CWE-125
  - CWE-401
vendor: gnu
product: tar
affected:
  - tar <= 1.33
published: '2021-03-26'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T21:17:33.373'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-20193'
references:
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=1917565'
    label: secalert@redhat.com
  - url: >-
      https://git.savannah.gnu.org/cgit/tar.git/commit/?id=d9d4435692150fa8ff68e1b1a473d187cc3fd777
    label: secalert@redhat.com
  - url: 'https://savannah.gnu.org/bugs/?59897'
    label: secalert@redhat.com
  - url: 'https://security.gentoo.org/glsa/202105-29'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=1917565'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://git.savannah.gnu.org/cgit/tar.git/commit/?id=d9d4435692150fa8ff68e1b1a473d187cc3fd777
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://savannah.gnu.org/bugs/?59897'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.gentoo.org/glsa/202105-29'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.01092
epssPercentile: 0.64371
ingestedAt: '2026-10-08T22:11:53.731Z'
---

## Overview

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.

## Affected

- `tar <= 1.33`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.