Ninja Forms Contact Form – The Drag and Drop Form Builder for WordPress <= 3.0.31 - Arbitrary Wordpress Shortcode Injection

2017-04-17 00:00
James Golovich

Strategic Overview

Status
Patched in 3.0.32
Affected Plugin
Ninja Forms – The Contact Form Builder That Grows With You
Affected Version
<= 3.0.31
CVSS
5.3Medium
Weakness type
CWE-94 · Improper Control of Generation of Code ('Code Injection')
CVE
CVE pending
View all Ninja Forms – The Contact Form Builder That Grows With You vulnerabilities

At a glance

This record tracks a medium-severity Improper Control of Generation of Code ('Code Injection') vulnerability in the Ninja Forms WordPress plugin, affecting versions <= 3.0.31. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 3.0.32; sites on affected versions should update now. Disclosed April 2017, reported by James Golovich.

Vulnerability Overview

The Ninja Forms Contact Form – The Drag and Drop Form Builder for WordPress plugin for WordPress is vulnerable to Arbitrary Wordpress Shortcode Injection in versions up to, and including, 3.0.31. This makes it possible for unauthenticated attackers to preview un-published forms and could possibly be used to leverage further attacks.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-94: Improper Control of Generation of Code ('Code Injection')

Reaching this weakness in Ninja Forms <= 3.0.31 takes a caller who can reach the endpoint. Code injection means input from a request reaches a language construct that evaluates code, so the attacker's text is executed rather than treated as data.

The injected code runs with the web server's privileges, giving the attacker the same access to the database and filesystem as WordPress itself. For Ninja Forms the fix is 3.0.32: builds <= 3.0.31 are affected, anything from 3.0.32 onward is not.

Remediation

Update to version 3.0.32, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Ninja Forms: WordSec's web application firewall inspects request payloads before WordPress loads them. Classes like this one can leave something behind, so the staged malware scanner is the second half: it looks for dropped files and modified code rather than for the request that created them. None of that substitutes for the fix: Ninja Forms 3.0.32 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Scanner
  • Alerts

External References

https://www.wordfence.com/threat-intel/vulnerabilities/id/f3ebaf25-1bd3-4770-b4bd-30de83b31add

Related records

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