Medium severity · published Oct 7, 2026
CVE-2026-86833
MetForm < 4.3.1 - Unauthenticated HTML Injection in Notification Emails via Field Shortcodes
5.4
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 5% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ME
MetForm ·
before 4.3.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-86833
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-86833
exploit
https://wpscan.com/vulnerability/6d6850d6-6fdf-4b97-9ccb-c90f9ed01ab0/
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