CVE-2018-6891

WordPress Online Booking and Scheduling Plugin – Bookly <= 14.5 - Cross-Site Scripting

2018-02-10 00:00
Luigi Gubello

Strategic Overview

Status
Patched in 14.6
Affected Plugin
Online Scheduling and Appointment Booking System – Bookly
Affected Version
<= 14.5
CVSS
7.2High
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2018-6891
View all Online Scheduling and Appointment Booking System – Bookly vulnerabilities

At a glance

CVE-2018-6891 is a high-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Online Scheduling and Appointment Booking System WordPress plugin, affecting versions <= 14.5. It carries a CVSS score of 7.2 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 14.6; sites on affected versions should update now. Disclosed February 2018, reported by Luigi Gubello.

Vulnerability Overview

The Online Booking and Scheduling plugin for WordPress is vulnerable to Cross-Site Scripting in versions up to, and including, 14.5. This is due to insufficient input sanitization and output escaping on the name parameter of a booking submission which makes it possible for unauthenticated attackers to inject arbitrary web scripts that execute in a victim's browser.

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

Reaching this weakness in Online Scheduling and Appointment Booking System <= 14.5 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 Online Scheduling and Appointment Booking System the fix is 14.6: builds <= 14.5 are affected, anything from 14.6 onward is not.

Remediation

Update to version 14.6, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Online Scheduling and Appointment Booking System: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Online Scheduling and Appointment Booking System 14.6 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2018-6891https://www.wordfence.com/threat-intel/vulnerabilities/id/4e3931c2-c9b4-412e-941d-840c5bb9be89https://nvd.nist.gov/vuln/detail/CVE-2018-6891

Related records

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