Arbitrary file upload in Muffingroup Betheme

CVE-2026-6261

The Betheme theme for WordPress is vulnerable to Arbitrary File Upload in versions up to, and including, 28.4. This is due to the upload_icons() function workflow moving and unzipping user-controlled ZIP files into a public uploads directory without validating extracted file types. This makes it possible for authenticated attackers, with author-level access and above, to upload arbitrary files (including PHP) and achieve remote code execution via the Icons icon-pack upload flow.

Vulnerability class: Unrestricted File Upload

Published · last modified .

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

EPSS: 0.006 (49.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 49.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-6261: held from 0.008 to 0.006.

EPSS over last 30 days · oldest: 0.008 · newest: 0.006 · change: -0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-6261?
CVE-2026-6261 is a high-severity vulnerability in Muffingroup Betheme, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.8/10. Published 2026-05-05.
How severe is CVE-2026-6261?
High severity. CVSS v3 base score is 8.8 out of 10.