CVE-2026-103911 wpmudev CVE debrief

Who should care

Defenders and administrators of WordPress installations using the Forminator Forms plugin should assess exposure and prioritize updates to prevent exploitation. This includes operators managing WordPress sites, platform administrators overseeing multiple installations, vulnerability management teams responsible for tracking and mitigating vulnerabilities, and security teams focused on protecting against potential shortcode execution attacks.

Why it matters

CVE-2026-103911 allows unauthenticated attackers to execute arbitrary shortcodes, potentially leading to various impacts. Defenders should prioritize verifying and updating Forminator Forms plugin versions.

• Verify and update Forminator Forms plugin versions to prevent exploitation.
• Monitor for suspicious activity, such as unusual shortcode executions.
• Implement additional security measures, like restricting access to sensitive pages.

Technical summary

The Forminator Forms – Contact Form, Payment Form & Custom Form Builder plugin for WordPress is vulnerable to arbitrary shortcode execution in all versions up to, and including, 1.58.1. 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.

Defensive priority

Defenders should prioritize verifying and updating Forminator Forms plugin versions to prevent exploitation.

Recommended defensive actions

• Verify and update Forminator Forms plugin versions to the latest secure version.
• Monitor for suspicious activity, such as unusual shortcode executions.
• Implement additional security measures, like restricting access to sensitive pages.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its CVSS score of 6.5 and MEDIUM severity. The vulnerability allows unauthenticated attackers to execute arbitrary shortcodes, potentially leading to various impacts.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.