Vulnerability in Smub Wpforms – Ai Form Builder For WordPress Contact Forms, Payment Survey Form, Quiz & More

CVE-2026-12127

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.

Vulnerability class: CRLF Injection

EPSS: 0.003 (26.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-12127?
CVE-2026-12127 is a medium-severity vulnerability in Smub Wpforms – Ai Form Builder For WordPress Contact Forms, Payment Survey Form, Quiz & More, classified under CRLF Injection. CVSS score: 5.3/10. Published 2026-07-01.
How severe is CVE-2026-12127?
Medium severity. CVSS v3 base score is 5.3 out of 10.