# CVE-2021-24031: libzstd1: In the Zstandard command-line utility prior to v1.4.1, output files were created with default permissions

CVE-2021-24031 is fixed in 2 products on 1 platform, first by libzstd1 1.3.3+dfsg-2ubuntu1.2, released February 19, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-24031
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0047
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 9, 2021

## Description

In the Zstandard command-line utility prior to v1.4.1, output files were created with default permissions. Correct file permissions (matching the input) would only be set at completion time. Output files could therefore be readable or writable to unintended parties.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libzstd1 Ubuntu 18.04.6 LTS (bionic) | 1.3.3+dfsg-2ubuntu1.2 | [libzstd1 1.3.3+dfsg-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libzstd1-1.3.3-dfsg-2ubuntu1.2.md) | Feb 19, 2021 |
| Linux | libzstd1 Ubuntu 20.04 LTS (focal) | 1.4.4+dfsg-3ubuntu0.1 | [libzstd1 1.4.4+dfsg-3ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libzstd1-1.4.4-dfsg-3ubuntu0.1.md) | Feb 19, 2021 |
| Linux | zstd Ubuntu 18.04.6 LTS (bionic) | 1.3.3+dfsg-2ubuntu1.2 | [zstd 1.3.3+dfsg-2ubuntu1.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-zstd-1.3.3-dfsg-2ubuntu1.2.md) | Feb 19, 2021 |
| Linux | zstd Ubuntu 20.04 LTS (focal) | 1.4.4+dfsg-3ubuntu0.1 | [zstd 1.4.4+dfsg-3ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-zstd-1.4.4-dfsg-3ubuntu0.1.md) | Feb 19, 2021 |

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