CVE-2026-12127 MEDIUM

CVE-2026-12127: WPForms <= 1.10.2 - Improper Neutralization of CRLF Sequences to Unauthenticated Email Header Injection via Reply-To Display Name

Vendor Smub
Product WPForms – AI Form Builder for WordPress – Contact Forms, Payment Forms, Survey Form, Quiz & More
Weakness CWE-93 · CRLF injection
Published July 1, 2026
Last update July 1, 2026

CVSS base score

5.3/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity Low

CVSS vector

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

What the vulnerability does

01Description

The WPForms – Easy Form Builder for WordPress – Contact Forms, Payment Forms, Surveys, & More plugin for WordPress is vulnerable to Improper Neutralization of CRLF Sequences ('CRLF Injection') in all versions up to, and including, 1.10.2 This is due to `get_reply_to_address()` processing the Reply-To display name through smart-tag expansion with context `'notification'` instead of `'notification-reply-to'`, which bypasses email-address validation while `wpforms_sanitize_textarea_field()` intentionally preserves CR/LF characters that are never stripped before the display name is concatenated into the raw `Reply-To:` mail header string. This makes it possible for unauthenticated attackers to inject arbitrary additional email headers — such as `Bcc:` — into outgoing notification emails, silently blind-copying all notification email copies to an attacker-controlled address. Exploitation requires that a form notification is configured to use a Paragraph Text (textarea) field as the Reply-To display name via a Smart Tag.

Explanation of Vulnerability in Simple Terms

02Summary

WPForms contains an integrity vulnerability affecting versions up to 1.10.2. An attacker on the network can modify data in transit without authentication or user interaction. The vulnerability has low integrity impact and does not affect confidentiality or availability. Update to a version newer than 1.10.2 to remediate.

What an attacker can do

03Attacker Capabilities

Modify form data or responses in transit without authentication.

Potential impact on your site

04Site Impact

Form submissions or data could be altered by attackers without your knowledge or consent.

Conditions required to exploit

05Prerequisites

Network access to the site; no authentication or user interaction required.

Key dates

06Disclosure timeline

July 1, 2026 CVE published
July 1, 2026 Record updated