CVE-2021-24673: Appointment Hour Booking < 1.3.16 - Authenticated Stored Cross-Site Scripting

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-10-04 · updated 2026-06-17
Weakness: CWE-79

Description

The Appointment Hour Booking WordPress plugin before 1.3.16 does not escape some of the Calendar Form settings, allowing high privilege users to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed.

Affected products

codepeople Appointment Hour Booking – Booking Calendar: before 1.3.16 — fixed in 1.3.16

How to fix

Upgrade to a fixed version: codepeople Appointment Hour Booking – Booking Calendar 1.3.16. Check the vendor advisory for mitigations.

References

https://wpscan.com/vulnerability/75a67932-d831-4dfb-a70d-a07650eaa755
https://wpscan.com/vulnerability/75a67932-d831-4dfb-a70d-a07650eaa755

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