CVE-2021-23956

MediumCVSS 6.5/10Last modified Jun 17, 2026

Description

An ambiguous file picker design could have confused users who intended to select and upload a single file into uploading a whole directory. This was addressed by adding a new prompt. This vulnerability affects Firefox < 85.

Metrics

CVSS 3.1 6.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Affected software

Vendor	Product	Versions
Mozilla	Firefox	< 85

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1338637Exploit, Issue Tracking, Patch, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-03/Release Notes, Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1338637Exploit, Issue Tracking, Patch, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-03/Release Notes, Vendor Advisory

Timeline

Published: Feb 26, 2021
Last modified: Jun 17, 2026
NVD status: Modified

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