PatchTheCVECVE-2026-100155: The The Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder plugin for
CVE-2026-100155 is a medium-severity flaw (CVSS 6.5) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
The The Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder plugin for WordPress is vulnerable to arbitrary shortcode execution in all versions up to, and including, 3.15.5 This is due to the software allowing users to execute an action that does not properly validate a value before running do_shortcode. This makes it possible for unauthenticated attackers to execute arbitrary shortcodes.
Why this priority
- Remotely exploitable, no login, no user action
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 6.5 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | n/a |
| CISA exploited list | No |
| Weakness | CWE-94 |
| Published | 2026-10-31 |
| Last modified | 2026-10-31 |
Last updated 2026-10-31 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Timeline
- Published CVE record published
- Updated Record last modified
Advisories and coverage
Research and news
- Vulners Bulletins: CVE-2026-100155 Ninja Forms <= 3.15.5 - Unauthenticated Arbitrary Shortcode Execution via 'formData' Field Value via Success Message Merge T 2026-10-31
- Vulners Bulletins: CVE-2026-100155 Ninja Forms <= 3.15.5 - Unauthenticated Arbitrary Shortcode Execution via 'formData' Field Value via Success Message Merge T 2026-10-31
- VulDB Recent Entries: CVE-2026-100155 | kstover Ninja Forms Plugin up to 3.15.5 on WordPress Shortcode do_shortcode code injection 2026-10-31
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-100155?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-100155 being exploited?
CVE-2026-100155 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-100155 affect?
CVE-2026-100155 affects affected software. Severity is medium (CVSS 6.5). The The Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder plugin for WordPress is vulnerable to arbitrary shortcode execution in all versions up to, and including, 3.15.5 This is due to the software
How urgent is CVE-2026-100155?
Priority 28/100. Remotely exploitable, no login, no user action