kstover Ninja Forms Plugin up to 3.15.5 on WordPress Shortcode Execution do_shortcode display_name code injection

Summaryinfo

A vulnerability has been found in kstover Ninja Forms Plugin up to 3.15.5 and classified as critical. Impacted is the function do_shortcode of the component Shortcode Execution. The manipulation of the argument display_name leads to code injection. This vulnerability is uniquely identified as CVE-2026-101326. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in kstover Ninja Forms Plugin up to 3.15.5 and classified as critical. This issue affects the function do_shortcode of the component Shortcode Execution. The manipulation of the argument display_name with an unknown input leads to a code injection vulnerability. Using CWE to declare the problem leads to CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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 authenticated attackers, with subscriber-level access and above, to execute arbitrary shortcodes. Exploitation requires that an administrator has configured at least one Ninja Forms field with its Default Value set to the {wp:user_display_name} merge tag on a publicly accessible page; a Subscriber need only set their display_name to a shortcode string via their profile and then visit that page.

It is possible to read the advisory at wordfence.com. The identification of this vulnerability is CVE-2026-101326 since 09/28/2026. The exploitation is known to be easy. The attack may be initiated remotely. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/31/2026). The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

• WordPress Plugin

Vendor

• kstover

Name

• Ninja Forms Plugin

Version

• 3.15.0
• 3.15.1
• 3.15.2
• 3.15.3
• 3.15.4
• 3.15.5

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CPE 2.2info

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