RCE in Create Block Theme

CVE-2026-16623

The Create Block WordPress plugin before 2.10.0 does not correctly escape user-supplied text before writing it into a generated PHP pattern file, allowing a multisite subsite administrator (who holds the capability gating this action but is denied the capability that normally gates PHP file editing) to inject and execute arbitrary PHP code on the server.

Vulnerability class: RCE (Remote Code Execution)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.0 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.005 (39.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.7% 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-2026-16623: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

  • Create Block Theme — versions 0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-16623?
CVE-2026-16623 is a high-severity vulnerability in Create Block Theme, classified under Code Injection. CVSS score: 8.0/10. Published 2026-08-04.
How severe is CVE-2026-16623?
High severity. CVSS v3 base score is 8.0 out of 10.