CVE-2026-86813

MetForm < 4.1.9 - Unauthenticated Email Header Injection via Notification Reply-To

The MetForm WordPress plugin before 4.1.9 does not properly neutralize newline characters in user-submitted values that are placed into notification email headers, allowing unauthenticated attackers to inject additional email headers, such as Bcc, into the emails the site sends when a submitted field value is configured to populate a header.

Affected

MetForm

CVSS v3.1 WPSCAN

4.8 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS

0.24% chance of exploitation in the next 30 days, 14th percentile

Published

2026-09-11

Proof-of-concept exploits (1)

• https://wpscan.com/vulnerability/afda2a26-b965-42cb-85a8-4a4d83ec026e/

References

• CVE Record
• NVD entry