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

Vulnerability summary

CVE-2026-12127 is a medium (CVSS 5.3) CRLF Injection vulnerability in smub wpforms – ai form builder for wordpress – contact forms, payment forms, survey form, quiz & more. EPSS estimates a 0.60% chance of exploitation in the next 30 days, higher than 47.7% of scored vulnerabilities. Fixed in 1.10.2.1.

Timeline

1. 01-07-2026
   PublishedVulnerability first disclosed.
2. 01-07-2026
   Last modifiedVulnerability information updated.

Description

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.

• CWE-93Improper Neutralization of CRLF Sequences ('CRLF Injection')The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.