CVE-2026-81283Network attack vectorHinoki check available

Subscriber-level code execution via unsafe meta deserialization

Published Sep 2, 2026 · Updated Sep 2, 2026

PHP object injection in weDevs WP User Frontend 4.3.10 and earlier allows remote authenticated users to execute code via frontend post editing. The frontend post edit form deserializes user-controlled field values from submitted post metadata when reopening a post. Subscriber access and a suitable installed POP chain are required for arbitrary PHP object instantiation to reach code execution.

CVSS severity8.8
High
EPSS probability0.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

PHP object injection in weDevs WP User Frontend 4.3.10 and earlier allows remote authenticated users to execute code via frontend post editing. The frontend post edit form deserializes user-controlled field values from submitted post metadata when reopening a post. Subscriber access and a suitable installed POP chain are required for arbitrary PHP object instantiation to reach code execution.

The record

CVE
CVE-2026-81283
Published
Sep 2, 2026
Updated
Sep 2, 2026
Vendor
HappyMonster
Product
WP User Frontend
Classifications
CWE-502, CAPEC-586, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 2, 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=n/a <=4.3.10 changes=[{"at":"4.3.11","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

HappyMonster · WP User Frontendversion=n/a <=4.3.10 changes=[{"at":"4.3.11","status":"unaffected"}]

Published CVSS scores

8.8PatchstackCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
CAPEC-586Object Injection
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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