CVE-2026-18331Network attack vector

Unauthenticated stored XSS via forged user identity

Published Aug 26, 2026 · Updated Aug 26, 2026

Stored XSS in Strategy11 Formidable Forms 6.33.1 and earlier allows remote attackers to execute scripts in administrators' browsers. The frm_user_id path accepts a forged administrator ID, leaving wp_kses_post() as the only filter before admin JavaScript decodes the stored value. An unauthenticated form submission is sufficient, and the payload runs when an administrator loads the affected entry, gaining script access to data and actions available in that browser context.

CVSS severity7.2
High
EPSS probability0.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Strategy11 Formidable Forms 6.33.1 and earlier allows remote attackers to execute scripts in administrators' browsers. The frm_user_id path accepts a forged administrator ID, leaving wp_kses_post() as the only filter before admin JavaScript decodes the stored value. An unauthenticated form submission is sufficient, and the payload runs when an administrator loads the affected entry, gaining script access to data and actions available in that browser context.

The record

CVE
CVE-2026-18331
Published
Aug 26, 2026
Updated
Aug 26, 2026
Vendor
Business Directory Team
Product
Formidable Forms
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=6.33.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Business Directory Team · Formidable Formsversion=0 <=6.33.1

Published CVSS scores

7.2WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript/JScript

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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