CVE-2026-57639

WP Booking System – Booking Calendar <= 2.1.0.6 - Unauthenticated Stored Cross-Site Scripting

2026-11-02 00:00
Sebi2030

Strategic Overview

Status
Patched in 2.1.0.7
Affected Plugin
WP Booking System – Booking Calendar
Affected Version
<= 2.1.0.6
CVSS
7.2High
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation
CVE
CVE-2026-57639
View all WP Booking System – Booking Calendar vulnerabilities

At a glance

CVE-2026-57639 is a high-severity Improper Neutralization of Input During Web Page Generation vulnerability in the WP Booking System WordPress plugin, affecting versions <= 2.1.0.6. 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 2.1.0.7; sites on affected versions should update now. Disclosed November 2026, reported by Sebi2030.

Vulnerability Overview

The WP Booking System – Booking Calendar plugin for WordPress is vulnerable to Stored Cross-Site Scripting in all versions up to, and including, 2.1.0.6. This is due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

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

Reaching this weakness in WP Booking System <= 2.1.0.6 takes no account at all. 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 WP Booking System the fix is 2.1.0.7: builds <= 2.1.0.6 are affected, anything from 2.1.0.7 onward is not.

Remediation

Update to version 2.1.0.7, or a newer patched version

How does WordSec protect against this?

Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: WP Booking System 2.1.0.7 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-57639https://www.wordfence.com/threat-intel/vulnerabilities/id/acb417ba-d16d-4dab-901a-d7cc48b43129https://nvd.nist.gov/vuln/detail/CVE-2026-57639

Related records

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