CVE-2026-80437: Ninja Forms arbitrary shortcode execution via request merge tags

CVE-2026-80437 · Severity: medium · CVSS 4.8 · Published 2026-09-06

Ninja Forms is a popular WordPress form-building plugin used to create contact forms and surveys on websites. A vulnerability in versions 3.14.10 through 3.15.1 allows unauthenticated visitors to execute any shortcode registered on the site by injecting malicious code through HTTP headers (like Client-IP or Referer), potentially enabling attackers to access sensitive data, modify site content, or inject malware without requiring authentication or admin privileges.

Quick answers

Is CVE-2026-80437 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-80437 being exploited in the wild.
How severe is CVE-2026-80437?
Medium severity, with a CVSS score of 4.8, published 6 September 2026.
Which products and versions are affected?
WP Ninjas Ninja Forms 3.14.10 through 3.15.1.
Is there a fix for CVE-2026-80437?
A patch was published on 2026-09-06: Fixed in version 3.15.2 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-80437 attacked?
It is attacked over the network.
Am I affected by CVE-2026-80437?
Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

This is a server-side template injection / code execution vulnerability in the Ninja Forms plugin's merge-tag substitution logic. When administrators configure form success messages or field default values to include request-derived merge tags (such as {other:user_ip}, {system:ip}, or {other:referer_url}), the plugin substitutes these values from HTTP request headers without sanitization, then processes the resulting content for shortcode execution. An unauthenticated attacker can inject a shortcode payload (e.g., [gallery]) via HTTP headers, which gets substituted into the message/field and then executed as a registered WordPress shortcode. Exploitation requires only that the administrator has configured one of the affected merge tags in a success message or default value; no authentication, nonce validation, or user interaction is required beyond a normal form submission or page load. The vulnerability was partially patched in 3.15.1 but remained exploitable through alternate merge-tag sources until the full fix in 3.15.2.

Affected products

  • WP Ninjas Ninja Forms 3.14.10 through 3.15.1

Timeline

  • 2026-09-04: disclosed
  • 2026-09-06: patched: Fixed in version 3.15.2

References

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