Vulnerability in Ninja Forms

CVE-2026-15256

The Ninja Forms WordPress plugin before 3.14.10 does not prevent user-supplied query-string input, used to pre-populate a form field's default value, from being processed as a shortcode, allowing unauthenticated attackers to execute arbitrary shortcodes registered on the site when a form so configured is embedded on a public page.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (15.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 16th percentile — 15.6% 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-2026-15256: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

  • Ninja Forms — versions 0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-15256?
CVE-2026-15256 is a medium-severity vulnerability in Ninja Forms, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 4.8/10. Published 2026-08-06.
How severe is CVE-2026-15256?
Medium severity. CVSS v3 base score is 4.8 out of 10.