CVE-2026-8143CWE-79

Booking Calendar – Event Calendar <= 2.1.6 - Unauthenticated Stored Cross-Site Scripting via Multiple Parameters

High · published May 27, 2026

CVSS v3.1
7.2
EPSS
0%
Percentile
23.5
In the wild
Unconfirmed
What it is

The HBook plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'hb_country_iso', 'hb_usa_state_iso', and 'hb_canada_province_iso' parameters in all versions up to, and including, 2.1.6 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 (the HBook Customers admin page).

The record
Technical detail
CVSS v3.1
7.2 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00318 · 23.5th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-05-27T06:46Z
EPSS history
Timeline
  • 27 MAY 06:46Z
    Booking Calendar – Event Calendar <= 2.1.6 - Unauthenticated Stored Cross-Site Scripting via Multiple Parameters
    cvelistv5