What is CVE-2026-16618?

CVE-2026-16618 is a critical-severity vulnerability in Improve Seo, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2026-08-04.

How severe is CVE-2026-16618?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Arbitrary file upload in Improve Seo

CVE-2026-16618

The Improve SEO WordPress plugin through 2.0.11 does not properly validate uploaded files, checking only the file content type while writing the file with the attacker-supplied extension into a publicly accessible directory, allowing unaut…

Vulnerability class: Unrestricted File Upload

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Unknown Improve Seo — versions 0

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

References

contact@wpscan.com (technical-description, exploit, vdb-entry)

Frequently asked questions

What is CVE-2026-16618?: CVE-2026-16618 is a critical-severity vulnerability in Improve Seo, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2026-08-04.
How severe is CVE-2026-16618?: Critical severity. CVSS v3 base score is 9.8 out of 10.