Arbitrary file upload in Foliovision Fv Player 8

CVE-2026-83526

The FV Player 8 plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 8.1.7 via the check_mimetype function. This is due to insufficient file type validation in check_mimetype(), which writes attacker-supplied remote file content to the public uploads directory before any MIME or extension check, combined with a missing capability check on new player creation. This makes it possible for authenticated attackers, with subscriber-level access and above, to upload files that may be executable, which makes remote code execution possible. This requires successfully exploiting a race condition.

Vulnerability class: Unrestricted File Upload

Published .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-83526?
CVE-2026-83526 is a high-severity vulnerability in Foliovision Fv Player 8, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.8/10. Published 2026-10-10.
How severe is CVE-2026-83526?
High severity. CVSS v3 base score is 8.8 out of 10.