CVE-2026-100155: kstover Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder

Ninja Forms <= 3.15.5 - Unauthenticated Arbitrary Shortcode Execution via 'formData' Field Value via Success Message Merge Tag

CVSS 6.5 MediumEPSS 0.0051 · 43rd percentile

Published by the CVE Program (CNA: Wordfence) at 31 Oct 2026, 05:33 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
kstover	Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder	affected 3.15.5 and earlier semver Other versions: unaffected

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.5	Medium	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N	CNA (Wordfence)

CISA KEV Not listed.
EPSS 0.0051, the 43rd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 05:33 UTC Confirmed by the CVE List
31 Oct 2026, 06:16 UTC Confirmed by NVD
31 Oct 2026, 20:00 UTC First seen by agentprime

Sources

References from the CNA

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.