CVE-2021-24031
In the Zstandard command-line utility prior to v1.4.1, output files were created with default permissions.
Does this matter?
Lower severity and a low EPSS score (0.46%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.46% probability · 40th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-277, CWE-276
- Affected
- facebook/zstandard
- Source
- cve-assign@fb.com
EPSS 0.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=981404Exploit, Issue Tracking, Mailing List, Third Party Advisory
- https://github.com/facebook/zstd/issues/1630Exploit, Issue Tracking, Third Party Advisory
- https://www.facebook.com/security/advisories/cve-2021-24031Vendor Advisory
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=981404Exploit, Issue Tracking, Mailing List, Third Party Advisory
- https://github.com/facebook/zstd/issues/1630Exploit, Issue Tracking, Third Party Advisory
- https://www.facebook.com/security/advisories/cve-2021-24031Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.