CVE-2026-86813
Medium
Description
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.
SeverityMedium
CVSS4.8
Exploit probability—
ProductMetForm
PublishedSep 11, 2026
First seenSep 11, 2026
Weakness typeCWE-93CWE-93
How to fix
Update
- MetForm4.1.9 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| MetForm | v < 4.1.9 | 4.1.9 |
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