---
id: CVE-2021-24032
title: >-
  Beginning in v1.4.1 and prior to v1.4.9, due to an incomplete fix for
  CVE-2021-24031, the Zstandard command-line utility created output files with
  default permissions and restricted those permissions immediately afterwards
summary: >-
  Beginning in v1.4.1 and prior to v1.4.9, due to an incomplete fix for
  CVE-2021-24031, the Zstandard command-line utility created output files with
  default permissions and restricted those permissions immediately afterwards.
  Output files …
severity: medium
cvss: 4.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-277
  - CWE-276
vendor: facebook
product: zstandard
affected:
  - 'zstandard >= 1.4.1, < 1.4.9'
patched:
  - zstandard 1.4.9
published: '2021-03-04'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T21:17:33.983'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-24032'
references:
  - url: 'https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=982519'
    label: cve-assign@fb.com
  - url: 'https://github.com/facebook/zstd/issues/2491'
    label: cve-assign@fb.com
  - url: 'https://www.facebook.com/security/advisories/cve-2021-24032'
    label: cve-assign@fb.com
  - url: 'https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=982519'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/facebook/zstd/issues/2491'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.facebook.com/security/advisories/cve-2021-24032'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
  - cve.org
epss: 0.00348
epssPercentile: 0.28298
ingestedAt: '2026-10-08T22:11:53.726Z'
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-08T20:59:25.866190Z'
---

## Overview

Beginning in v1.4.1 and prior to v1.4.9, due to an incomplete fix for CVE-2021-24031, the Zstandard command-line utility created output files with default permissions and restricted those permissions immediately afterwards. Output files could therefore momentarily be readable or writable to unintended parties.

## Affected

- `zstandard >= 1.4.1, < 1.4.9`

## Remediation

Upgrade past the affected range:

- `zstandard 1.4.9`