CVE-2026-86838

Bookly <= 28.2 - Unauthenticated Payment Bypass

2026-09-25 00:00

Strategic Overview

Status: Patched in 28.3
Affected Plugin: Online Scheduling and Appointment Booking System – Bookly
Affected Version: <= 28.2
CVSS: 5.3Medium
Weakness type: CWE-602 · Client-Side Enforcement of Server-Side Security
CVE: CVE-2026-86838

View all Online Scheduling and Appointment Booking System – Bookly vulnerabilities

At a glance

CVE-2026-86838 is a medium-severity Client-Side Enforcement of Server-Side Security vulnerability in the Online Scheduling and Appointment Booking System WordPress plugin, affecting versions <= 28.2. 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 28.3; sites on affected versions should update now. Disclosed September 2026, reported by vuxvinh.

Vulnerability Overview

The Bookly plugin for WordPress is vulnerable to Payment Bypass in all versions up to, and including, 28.2. This is due to a lack of server-side payment verification. This makes it possible for unauthenticated attackers to bypass payments.

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 28.3, 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: Online Scheduling and Appointment Booking System 28.3 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-86838 https://www.wordfence.com/threat-intel/vulnerabilities/id/6cad50b5-5485-4efb-a511-9ec057cf0a28 https://nvd.nist.gov/vuln/detail/CVE-2026-86838

Related records

Other vulnerabilities in Online Scheduling and Appointment Booking System – Bookly

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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