All vulnerabilities
CVE-2026-14556

HappyForms < 1.26.15 - Unauthenticated HTML Injection in Admin Notification Email via client_referer

Unknown HappyForms
CVSS
5.4Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.15%Chance of exploitation activity in the next 30 days, higher than 4% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in1.26.15Fixed versionCVE List
Published21 Oct 2026Updated 21 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 HappyForms WordPress plugin before 1.26.15 does not sanitise or escape a user-controlled referral value before embedding it in the form notification email, allowing unauthenticated attackers to inject arbitrary HTML into the emails site administrators receive.

Text from CVE List

Affected versions 1

  • HappyFormsaffected: all versions before 1.26.15CVE List

References 1