Email Header Injection in JetFormBuilder Plugin by WordPress
CVE-2026-19862

4.8MEDIUM

Key Information:

Vendor

WordPress
Status
Jetformbuilder
Vendor
CVE Published:
6 September 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-19862?

The JetFormBuilder plugin for WordPress, prior to version 3.6.5.2, contains a vulnerability allowing unauthenticated users to manipulate email headers through unvalidated address values sourced from form submissions. This flaw permits the injection of arbitrary email headers, facilitating hidden recipient additions and sender spoofing, provided the WordPress site is configured to take any email address from user input. Proper input validation is necessary to mitigate the risks associated with this vulnerability.

Affected Version(s)

JetFormBuilder 0 < 3.6.5.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-19862 - Proof of Concept

References

https://wpscan.com/vulnerability/b3fe5552-6736-4479-9c61-...
exploitvdb-entrytechnical-description

CVSS V3.1

Score:
4.8
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Emirhan Kurt
WPScan
.