CVE-2026-87071Network attack vectorHinoki check available

Unauthorized post metadata writes via unrestricted keys

Published Sep 23, 2026 · Updated Sep 23, 2026

Improper input validation in WPMU DEV Forminator Forms before 1.57.2.1 allows remote attackers to attach arbitrary metadata to submitted posts. The public post-submission path accepts caller-selected metadata keys without excluding WordPress-reserved keys before storing the submission-created post. Exploitation requires an unauthenticated submission to a public form configured to collect post content, and the bounded result is unauthorized modification of that created post's metadata.

CVSS severity5.3
Medium
EPSS probability0.19%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Improper input validation in WPMU DEV Forminator Forms before 1.57.2.1 allows remote attackers to attach arbitrary metadata to submitted posts. The public post-submission path accepts caller-selected metadata keys without excluding WordPress-reserved keys before storing the submission-created post. Exploitation requires an unauthenticated submission to a public form configured to collect post content, and the bounded result is unauthorized modification of that created post's metadata.

The record

CVE
CVE-2026-87071
Published
Sep 23, 2026
Updated
Sep 23, 2026
Vendor
WPMU DEV
Product
Forminator Forms
Classifications
CWE-20, T1565.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 23, 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 <1.57.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

WPMU DEV · Forminator Formsversion=0 <1.57.2.1

Published CVSS scores

5.3WPScanCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

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