What’s Vulnerable › Vulnerabilities

CVE-2026-8143: Booking Calendar – Event Calendar <= 2.1.6 - Unauthenticated Stored Cross-Site Scripting via Multiple Parameters

• Severity: high (CVSS 7.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-05-27 · updated 2026-06-17
• Weakness: CWE-79

Description

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).

Affected products

• omnivo Booking Calendar – Event Calendar: through 2.1.6

References

• https://codecanyon.net/item/hbook-hotel-booking-system-wordpress-plugin/15059946
• https://www.wordfence.com/threat-intel/vulnerabilities/id/e1c16bcb-c188-4e01-9d0b-e4e1a1ef82ee?source=cve

Get alerted when CVE-2026-8143 or the next vulnerability affects your stack