What’s Vulnerable › Vulnerabilities
CVE-2026-86833: MetForm < 4.3.1 - Unauthenticated HTML Injection in Notification Emails via Field Shortcodes
- Severity: medium (CVSS 5.4 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-10-07 · updated 2026-10-07
- Weakness: CWE-74
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.
Affected products
- MetForm: before 4.3.1 — fixed in 4.3.1
How to fix
Upgrade to a fixed version: MetForm 4.3.1. Check the vendor advisory for mitigations.
References
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