CVE-2026-49768 CRITICAL

CVE-2026-49768: WordPress Happyforms plugin <= 1.26.13 - PHP Object Injection vulnerability

Vendor Happyforms

Product Happyforms

Weakness CWE-502 · Unsafe deserialization

Published June 15, 2026

Last update June 15, 2026

View on NVD All CVEs

CVSS base score

9.8/10

Attack vector Network

Attack complexity Low

Privileges required None

User interaction None

Confidentiality High

Integrity High

CVSS vector

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

What the vulnerability does

01Description

Unauthenticated PHP Object Injection in Happyforms <= 1.26.13 versions.

Explanation of Vulnerability in Simple Terms

02Summary

Happyforms versions up to 1.26.13 contain a deserialization vulnerability that allows unauthenticated attackers to execute arbitrary code on the site. The vulnerability exists in how the plugin processes untrusted serialized data without proper validation. An attacker can exploit this remotely without user interaction to gain full control of the site.

What an attacker can do

03Attacker Capabilities

Run their own code on the site and take complete control without needing a user account.

Potential impact on your site

04Site Impact

Complete site compromise: attackers can steal data, modify content, install malware, or take the site offline.

Conditions required to exploit

05Prerequisites

Network access only; no authentication or user interaction required.

Key dates

06Disclosure timeline

June 15, 2026 CVE published

External resources

07References

NVD — National Vulnerability Database https://nvd.nist.gov/vuln/detail/CVE-2026-49768 CWE — Common Weakness Enumeration https://cwe.mitre.org/data/definitions/502.html AskarLabs — CWE-502 write-up Deserialization of Untrusted Data

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