Auth bypass in Murgroland Wp Booking System – Calendar

CVE-2026-116557

The WP Booking System - Booking Calendar plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the wpbs_action_ajax_calendar_remove_note() function in versions up to, and including, 2.1.0.5 This makes it possible for authenticated attackers, with Subscriber-level access and above, to delete arbitrary calendar notes belonging to any calendar.

Vulnerability class: Broken Access Control

Published .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (28.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 28.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-116557?
CVE-2026-116557 is a critical-severity vulnerability in Murgroland Wp Booking System – Calendar, classified under Missing Authorization. CVSS score: 9.1/10. Published 2026-10-31.
How severe is CVE-2026-116557?
Critical severity. CVSS v3 base score is 9.1 out of 10.