Ultimate Addons for WPBakery <= 3.16.11 - Stored Cross-Site Scripting

2017-04-16 00:00
WpHutte

Strategic Overview

Status
Patched in 3.16.12
Affected Plugin
Ultimate Addons for WPBakery
Affected Version
<= 3.16.11
CVSS
9.8Critical
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE pending
View all Ultimate Addons for WPBakery vulnerabilities

At a glance

This record tracks a critical-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Ultimate Addons for WPBakery WordPress plugin, affecting versions <= 3.16.11. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 3.16.12; sites on affected versions should update now. Disclosed April 2017, reported by WpHutte.

Vulnerability Overview

The Ultimate Addons for WPBakery plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the tab parameter in versions up to, and including 3.16.11 via the update_ultimate_options AJAX action and ultimate_smooth_scroll_options[step] parameter. This makes it possible for low-level authenticated attackers to inject arbitrary web scripts in administrative pages that execute whenever a user accesses the page with the stored web scripts.

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. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

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

Reaching this weakness in Ultimate Addons for WPBakery <= 3.16.11 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 Ultimate Addons for WPBakery the fix is 3.16.12: builds <= 3.16.11 are affected, anything from 3.16.12 onward is not.

Remediation

Update to version 3.16.12, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Ultimate Addons for WPBakery: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Ultimate Addons for WPBakery 3.16.12 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.wordfence.com/threat-intel/vulnerabilities/id/6b48cae6-254c-4882-a464-3a44a63cadf5

Related records

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