CVE-2018-14846

Multi Step Form <= 1.2.5 - Stored Cross-Site Scripting

2018-07-27 00:00
Mohammed Ansari

Strategic Overview

Status
Patched in 1.2.6
Affected Plugin
Multi Step Form
Affected Version
< 1.2.6
CVSS
6.4Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2018-14846
View all Multi Step Form vulnerabilities

At a glance

CVE-2018-14846 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Multi Step Form WordPress plugin, affecting versions < 1.2.6. It carries a CVSS score of 6.4 (reachable over the network; low attack complexity). The issue is fixed in version 1.2.6; sites on affected versions should update now. Disclosed July 2018, reported by Mohammed Ansari.

Vulnerability Overview

The Mondula Multi Step Form plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘fw_wizard_save’ action in versions up to, and including, 1.2.5 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The following parameters are affected: data[wizard][steps][0][title] data[wizard][steps][0][headline] data[wizard][steps][0][copy_text] data[wizard][steps][0][parts][0][title] data[wizard][steps][0][parts][0][blocks][0][label] data[wizard][steps][0][parts][0][blocks][0][format] data[wizard][steps][0][parts][0][blocks][1][label] data[wizard][steps][0][parts][0][blocks][2][label] data[wizard][steps][0][parts][0][blocks][3][label] data[wizard][settings][thankyou].

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 interaction from a victim user.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Multi Step Form < 1.2.6 carries this weakness at fw_wizard_save, and reaching it takes a caller who can reach the endpoint. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For Multi Step Form the fix is 1.2.6: builds < 1.2.6 are affected, anything from 1.2.6 onward is not.

Remediation

Update to version 1.2.6, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Multi Step Form: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Multi Step Form 1.2.6 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2018-14846https://www.wordfence.com/threat-intel/vulnerabilities/id/fe668f93-f6b7-4824-ad17-024291d8f535https://nvd.nist.gov/vuln/detail/CVE-2018-14846

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C