CVE-2026-19862

JetFormBuilder — Dynamic Blocks Form Builder < 3.6.5.2 - Unauthenticated Email Header Injection

2026-09-03 00:00

Strategic Overview

Status: Patched in 3.6.5.2
Affected Plugin: JetFormBuilder — Dynamic Blocks Form Builder
Affected Version: < 3.6.5.2
CVSS: 5.3Medium
Weakness type: CWE-113 · Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
CVE: CVE-2026-19862

View all JetFormBuilder — Dynamic Blocks Form Builder vulnerabilities

At a glance

CVE-2026-19862 is a medium-severity Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting') vulnerability in the JetFormBuilder WordPress plugin, affecting versions < 3.6.5.2. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 3.6.5.2; sites on affected versions should update now. Disclosed September 2026, reported by Emirhan Kurt.

Vulnerability Overview

The JetFormBuilder — Dynamic Blocks Form Builder plugin for WordPress is vulnerable to Email Header Injection in all versions up to 3.6.5.2 (exclusive). This makes it possible for unauthenticated attackers to inject arbitrary email headers.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-113: Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

The product receives data from an HTTP agent/component (e.g., web server, proxy, browser, etc.), but it does not neutralize or incorrectly neutralizes CR and LF characters before the data is included in outgoing HTTP headers.

Remediation

Update to version 3.6.5.2, or a newer patched version

How does WordSec protect against this?

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: JetFormBuilder 3.6.5.2 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-19862 https://www.wordfence.com/threat-intel/vulnerabilities/id/11d5f187-e919-43f6-88c7-db5ffa6bd793 https://nvd.nist.gov/vuln/detail/CVE-2026-19862

Related records

Other vulnerabilities in JetFormBuilder — Dynamic Blocks Form Builder

CVSS Vector

5.3

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityLow
AvailabilityNone

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