CVE-2026-16282

Appointment Hour Booking <= 1.5.87 - Unauthenticated Price Manipulation

2026-08-03 00:00

Strategic Overview

Status: Patched in 1.5.88
Affected Plugin: Appointment Hour Booking – Booking Calendar
Affected Version: <= 1.5.87
CVSS: 5.3Medium
Weakness type: CWE-602 · Client-Side Enforcement of Server-Side Security
CVE: CVE-2026-16282

View all Appointment Hour Booking – Booking Calendar vulnerabilities

At a glance

CVE-2026-16282 is a medium-severity Client-Side Enforcement of Server-Side Security vulnerability in the Appointment Hour Booking WordPress plugin, affecting versions <= 1.5.87. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 1.5.88; sites on affected versions should update now. Disclosed August 2026, reported by Alessandro Greco.

Vulnerability Overview

The Appointment Hour Booking plugin for WordPress is vulnerable to Price Manipulation in versions up to, and including, 1.5.87. This is due to the extract_appointments function accepting a user-supplied price via the tcost parameter (stored as $fieldpostedcost) and assigning it directly to the booking record, exploitable by unauthenticated users who could also trigger the vulnerable code path by posting bccf_payment_option_paypal=0. This makes it possible for unauthenticated attackers to manipulate the final booking price by submitting an arbitrary cost value, bypassing server-side price enforcement.

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-602: Client-Side Enforcement of Server-Side Security

The product is composed of a server that relies on the client to implement a mechanism that is intended to protect the server.

Remediation

Update to version 1.5.88, or a newer patched version

How does WordSec protect against this?

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: Appointment Hour Booking 1.5.88 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-16282 https://www.wordfence.com/threat-intel/vulnerabilities/id/d665df2d-5217-4a23-9278-5b88162f7d13 https://nvd.nist.gov/vuln/detail/CVE-2026-16282

Related records

Other vulnerabilities in Appointment Hour Booking – Booking Calendar

CVSS Vector

5.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityLow
AvailabilityNone

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