All vulnerabilities
CVE-2026-86833

MetForm < 4.3.1 - Unauthenticated HTML Injection in Notification Emails via Field Shortcodes

Unknown MetForm
Open in ThreatlineRecord JSON
CVSS
5.4Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.16%Chance of exploitation activity in the next 30 days, higher than 5% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in4.3.1Fixed versionCVE List
Published7 Oct 2026Updated 7 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

The MetForm WordPress plugin before 4.3.1 does not sanitize or escape submitted form-field values before inserting them into the HTML body of its email notifications, allowing unauthenticated attackers to inject arbitrary markup into the administrator and submitter notification emails the site sends.

Text from CVE List

Affected versions 1

  • MetFormaffected: all versions before 4.3.1CVE List

References 1